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category: literaturenote citekey: paloczandresendecreasingfuelconsumptionexhaust2013 title: Decreasing Fuel Consumption and Exhaust Gas Emissions in Transportation authors: "Palocz-Andresen, Michael" year: 2013 date: 2013-00-00 2013 doi: 10.1007/978-3-642-11976-7 url: "https://doi.org/10.1007/978-3-642-11976-7" zotero_key: V8698Q54 zotero_storage: KXTNTDJJ collections: transpordi_planeerimine folder: 001_artiklid firstAuthor: "Palocz-Andresen, Michael"

status: converted

For further volumes: http://www.springer.com/series/8059

Decreasing Fuel Consumption and Exhaust Gas Emissions in Transportation

Sensing, Control and Reduction of Emissions

Michael Palocz-Andresen UCS Umweltconsulting Hamburg Germany

ISSN 1865-3529 ISSN 1865-3537 (electronic) ISBN 978-3-642-11975-0 ISBN 978-3-642-11976-7 (eBook) DOI 10.1007/978-3-642-11976-7

Springer Heidelberg New York Dordrecht London Library of Congress Control Number: 2012935235

-Springer-Verlag Berlin Heidelberg 2013

This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher's location, in its current version, and permission for use must always be obtained from Springer. Permissions for use may be obtained through RightsLink at the Copyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law.

The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use.

While the advice and information in this book are believed to be true and accurate at the date of publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the material contained herein.

Printed on acid-free paper

Springer is part of Springer Science+Business Media (www.springer.com)

Preface

Since 1998, the introduction of the first Directive with On-Board Measurement in the EU, many parameters in transport have changed. Both the population of the world and the demand for transportation have been continuously increasing. Transport has become the basic foundation of the economy in all countries. In the course of this process, the environment and the climate have been changing in a remarkable way and in turn have influenced transport.

Environmental legislation with Directives such as 98/69/EU, 99/96/EU, and finally 582/2011/EC with amendments, is already reducing emissions of individual vehicles. However, the number of motor vehicles, ships, and airplanes is rapidly rising, especially in fast developing countries. Parallel to this, the amount of oil products consumed and the mass of pollutants emitted are intensively increasing.

A new, sustainable path is required, which focuses on reasonable mass transport at a reasonable price, short travel times with optimal connections, positive impacts in safety, and improvements in sustainability. Good examples are needed worldwide.

Transportation could be improved with the introduction of carbon taxes, higher fuel efficiency standards and the use of new kinds of fuels. It is not enough to produce biogenic and synthetic fuels, although they can be optimally used in road vehicles, airplanes and ships, because they have their own additional problems. On the one side, their utilization lowers the consumption of fossil fuels, but on the other side, their exaggerated use could contribute to the destruction of agriculture and the landscape.

Transport burns most of the petroleum of the world and emits the most air pollution, including unburned hydrocarbons, carbon monoxide, nitrous oxides, and particles. It is the fastest growing consumption and emission sector on Earth. This leads to significant environmental and health problems especially in large cities and is a major contributor to global warming because of emissions of carbon dioxide. New urban infrastructure needs to primarily foster environmentally friendly modes and better management of transportation.

Vehicles, airplanes and ships are becoming more and more efficient, i.e., lighter and more intelligent, with improved aerodynamics, optimized design, and higher vi Preface

performance. But can technology reduce fuel consumption and emissions effectively?

While technological development has created many problems, such as climate change and loss of resources, at the same time it is part of the solution. The higher demand for transportation could be fulfilled with the assistance of new technologies, new materials and highly intelligent hardware and software systems. Additionally, navigation and active communication systems can optimally and safely regulate the increasing traffic.

The higher comfort level and safety of new vehicles, airplanes and ships also contributes to more sustainability in transportation. However, improved infrastructure is often combined with increased traffic density and higher emissions. That is the reason why research and technological development have to survey alternative technologies and pilot projects to provide sustainable urban development and improve the potentials of mass transportation.

Regarding fuel consumption and emission characteristics, regulations have been intensively expanded in the last 20 years. Energy use and emissions vary greatly between several modes of transportation. Electrification and energy efficiency of transport must be increased in the next decades. However, the introduction of new technology will not happen suddenly but only gradually.

Less than optimal measures to order intensive fuel saving could cause major economic losses. Fuel substitution in transportation has high investment costs in comparison to other sectors of the economy. Therefore, besides technology, a sustainable strategy requires the increased use of renewable energy resources, worldwide intelligent navigation measures, common international regulations, and voluntary agreements between governments, civil, and international organizations limiting fuel consumption and exhaust gas emissions.

The topic of this book is the comprehensive consideration of all aspects of intelligent fuel consumption and exhaust gas emissions in transportation. It can be recommended as a source for the stimulation of further discussions to anyone interested in the field of sustainable transportation.

Lüneburg, winter 2011 Prof. Dr. Wolfgang Ruck

Acknowledgments

Three years ago, 2008, my first book concerning On-Board Measurement was published by the Expert Verlag in Renningen, Germany. In that book the basic fundamentals of direct measurement technology (OBM) were described. Since that time, the legislation and the technology have been intensively developed. It seems to be necessary, to continue the work. The next logical stage of On-Board Measurement is Self Diagnosis (SD) which is the centre of consideration in this book.

This is the result of three and a half years of work. Special thanks go to the researchers and teachers, scientists and professors of Leuphana University Lüneburg for the invaluable advice and support regarding sustainable transportation.

The consortium of the University of West-Hungary Sopron supported several application-oriented sections in research and presentation and also gave important assistance.

Within my own team, I would like to express my gratitude to Mr. János Székely (Budapest), Mr. Balázs Szegedi, Ms. Luca Héjja, and Mr. Gergely Krizbai (Sopron) for their efforts in the area of design, Mrs. Dóra Szalay (Sopron) for her support in the construction and checking of units and conversions in the book, and Dr. Hartmut Mädler and Mr. Ulrich Gross (Hamburg) in the translation of subtexts in the international literature and creation of subject indices.

I would also like to heartily thank Dr. Huba Németh (Budapest) for his kind assistance and cooperation with regard to road technology.

I am also grateful to Mr. Károly Galvácsy and Mr. János Mikulás (Budapest) for their support in the development of aviation and for many interesting discussions regarding safety, aircraft inspection, and maintenance and air traffic emissions.

Concerning the shipping experiments undertaken for the purpose of this book, Mr. Joachim Goetze (Hamburg) and Mr. Csaba Hargitai (Budapest) were also extremely helpful.

viii Acknowledgments

And finally, many thanks to Dr. Richard von Fuchs (Sopron) and Mr. David Carolan Kômoto (Hamburg) for proofreading this book.

Hamburg, winter 2011 Prof. Dr.-Ing. habil. Michael Palocz-Andresen

Contents

| Basics | of
Fuel
Consumption
and
Exhaust
Gas
Emissions
| | |--------|-----------------------------------------------------------------------|--| | 1.1 | Comparison
of
Fuel
Consumption
and
Emissions | | | | in
Transportation | | | 1.2 | Principle
of
Continuous
Controlling
Combustion
Process | | | 1.3 | Legislation
Frame
Conditions. | | | | 1.3.1
Lack
of
Micro
Sensors
and
Micro | | | | Controller
Systems | | | | 1.3.2
Variability
of
Real
Travel
Conditions | | | 1.4 | Conversion
of
Real
Operation
Emissions
to | | | | Test
Bench
Emissions | | | 1.5 | Specific
Characteristics
of
Vehicles',
Airplanes' | | | | and
Ships'
Emissions | | | 1.6 | Summary
and
Recommendations:
Basics
of
Intelligent | | | | | | | | | | | | Monitoring
of
Fuel
Consumption
and
Emissions | | | | References | | | Fuels | in
Transportation | | | 2.1 | Classification
of
Types
of
Fuels | | | 2.2 | Road
Transport
Fuels | | | | 2.2.1
Gasoline | | | | | | | | 2.2.2
Diesel
Fuel | | | | 2.2.3
Reference
Fuels | | | | 2.2.4
Products
of
Natural
Gas | | | | 2.2.5
Synthetic
Fuels. | | | | 2.2.6
Biogenic
Fuels | | | | 2.2.7
Blended
Fuels | | | 2.3 | Aviation
Fuels
2.3.1
Kerosene | |

x Contents

2.3.3 Alternative
Fuels
to
Kerosene
in
Aviation		 25
2.4 Marine Fuels 27
2.4.1 Marine
Distillate
Fuels		 27
2.4.2 Heavy
Fuel
Oil.		 28
2.5 Summary and
Recommendations:
Fuels
in
Transportation		 29
2.5.1 Fuels
in
Road
Transportation		 29
2.5.2 Fuels
in
Aviation		 30
2.5.3 Fuels
in
Maritime
Shipping		 30
References 31
3 Construction of
Transportation
Means		 33
3.1 Road Vehicles 33
3.1.1 Main
Construction
Elements
of
Cars.		 34
3.1.2 Classification
of
Vehicles		 34
3.1.3 Influence
of
Light
Weight
Construction
on
Fuel
Consumption		 40
3.2 Airplanes. 41
3.2.1 Main
Construction
Elements		 44
3.2.2 Classification
of
Airplanes.		 44
3.2.3 Comparison
of
Fuel
Consumption
and
Exhaust
Gas
Emissions
from
Airplane
Types		 44
3.3 Influence of
Weight
Reduction
on
Fuel
Consumption		 46
3.3.1 Optimization
of
Takeoff
Mass		 47
3.3.2 Use
of
New
Construction
Materials		 47
3.4 Construction of
Ships		 51
3.4.1 Main
Construction
Elements		 52
3.4.2 Classification
of
Ships.		 52
3.4.3 Type
of
Ships		 52
3.4.4 Comparison
of
Fuel
Consumption
of
Ships		 52
3.4.5 Influence
of
New
Construction
Principles
on
the
Fuel
Consumption.		 53
3.5 Summary and
Recommendations:
Construction
Technology.		 55
3.5.1 Road
Vehicles		 55
3.5.2 Airplanes. 55
3.5.3 Ships. 56
References 56
4 Fuel System and
Fuel
Measurement		 59
4.1 Fuel System
in
Vehicles		 60
4.1.1 Fuel
Measurement		 61
4.2 Fuel System
in
Airplanes.		 65
4.2.1 Fuel
Storage
and
Supply		 65
4.2.2 Fuel
Regulation		 66
4.2.3 Fuel
Planning.		 67

Contents xi

4.2.4 Notes
on
ETOPS
and
Additional
Fuel.		 69
4.3 Fuel Systems
in
Ships		 70
4.3.1 Fuel
Preparation
and
Fuel
Supply.		 70
4.3.2 Fuel
Measurement
on
Ships		 72
4.3.3 Fuel
Planning
on
Ships		 73
4.3.4 CO2
Index
Data
Analysis		 75
4.4 Summary and
Recommendations:
Fuel
System
and
Fuel		 Measurement 75
References 77
5 Emissions. 81
5.1 Physical and
Chemical
Properties
of
Combustion
Products		 81
5.2 Measurement
of
Emissions		 83
5.2.1 Measurement
at
Test
Benches		 84
5.2.2 Measurement
On-Board.		 85
5.2.3 Remote
Sensing
Technology		 87
5.3 Emissions in
Road
Traffic		 87
5.4 Emissions in
Aviation		 88
5.5 Emissions in
Ship
Navigation		 90
5.6 Summary and
Recommendations:
Emissions
from Transportation 91
5.6.1 Vehicle
Emissions		 92
5.6.2 Airplane
Emissions		 92
5.6.3 Ship
Emissions.		 93
References 93
6 Electronic Systems
and
Computer
Technology.		 95
6.1 Construction of
Electronic
Systems.		 95
6.2 Vehicles' Electronics 97
6.2.1 Electronic
Control
Unit		 97
6.2.2 Controller
Area
Network
Bus.		 98
6.2.3 Structure
of
Diagnosis.		 98
6.3 Airplanes' Electronics 99
6.3.1 Flight
Management
Systems		 99
6.3.2 Engine
Monitoring
System		 101
6.3.3 Airplane
Instruments.		 101
6.4 Ships' Electronics. 102
6.4.1 Integrated
Bridge
System.		 103
6.4.2 Elements
of
Ship
Electronics		 104
6.4.3 Vessel
Traffic
Service
and
Automatic
Identification
System		 104
6.5 Summary and
Recommendations:
Electronic
Systems
and Computer
Technology
in
Transportation		 105
6.5.1 Electronic
Technology
in
Vehicles		 105

xii Contents

6.5.2 Electronic
Technology
in
Airplanes		 106
6.5.3 Electronic
Technology
in
Ships		 106
References 107
7 Aerodynamics of
Vehicles
and
Airplanes,
and
Hydrodynamics
of Ships 109
7.1 Aerodynamics
of
Vehicles		 109
7.1.1 Air
Resistance		 109
7.1.2 Relation
Between
Speed
and
Fuel
Consumption.		 110
7.1.3 Rolling
Resistance		 111
7.2 Aerodynamics
of
Airplanes		 111
7.2.1 Laminar
Flow		 112
7.2.2 Nacelle
Efficiency		 112
7.2.3 Airframe
Concepts
with
Advanced
Aerodynamics		 113
7.2.4 Wingtips
and
Riblets.		 113
7.3 Hydro- and
Aerodynamics
of
Ships		 114
7.3.1 Floating
on
a
Cushion
of
Air		 115
7.3.2 Inland
Shipping		 116
7.4 Summary and
Recommendations:
Technical
Results
in
Aero
and Hydrodynamics 117
7.4.1 Aerodynamics
of
Vehicles		 118
7.4.2 Aerodynamics
of
Airplanes		 118
7.4.3 Hydrodynamics
of
Ships		 118
References 119
8 Propulsion Systems. 121
8.1 Propulsion Elements
in
Road
Vehicles		 121
8.2 Operating Functions
of
the
Propulsion		 122
8.2.1 Gear
Choice.		 122
8.2.2 Auxiliary
Equipment.		 123
8.2.3 Energy
Dissipation		 124
8.2.4 Thermal
Efficiency		 124
8.3 Propulsion of
Airplanes.		 125
8.3.1 Integration
of
Airframe
and
Engine		 126
8.3.2 Retrofitting
Old
Engines		 127
8.3.3 Thermal
Efficiency		 127
8.4 Propulsion of
Ships.		 128
8.4.1 Propeller
Systems		 128
8.4.2 New
Propeller
Technology		 129
8.4.3 Start
and
Stop
System		 131
8.5 Summary and
Recommendations:
Propulsion
Systems		 131
8.5.1 Propulsion
of
Vehicles		 131
8.5.2 Propulsion
of
Airplanes.		 132
8.5.3 Propulsion
of
Ships.		 132
References 133

Contents xiii

9 Vehicle Engines 135
9.1 Principles
of
Operation		 135
9.2 Operation
of
Spark
and
Self
Ignition
Engines		 137
9.2.1
Spark
Ignition
Engines		 138
9.2.2
Self
Ignition
Engine		 138
9.3 Summary
and
Recommendations:
Vehicle
Engine
Technology		 145
References 146
10 Airplane Engines 149
10.1 Types
of
Engines		 149
10.2 Fuel
Consumption
and
Thrust		 152
10.3 Construction
of
the
Combustion
Chamber		 152
10.4 Emissions
from
the
Combustion
Chamber		 153
10.5 Measurement
in
Turbofan
Engines		 154
10.6 Summary
and
Recommendations:
Combustion
Process
in
a
Jet
Engine		 156
References 156
11 Marine Diesel
Engines		 159
11.1 Fuel
Consumption
in
Marine
Diesel
Engines		 159
11.2 Engine
Operation		 161
11.2.1
Slow
Speed
Two-Stroke
Marine
Diesel
Engines.		 162
11.2.2
Medium
Speed
Four-Stroke
Marine
Diesel
Engines		 162
11.2.3
High
Speed
Four-Stroke
Marine
Diesel
Engines.		 162
11.3 Main
Operation
Characteristics
of
Marine
Diesel
Engines		 163
11.3.1
Charging
Marine
Diesel
Engines		 163
11.3.2
Operation
in
Changing
Environment
Conditions.		 164
11.3.3
Impact
of
Bad
Weather
on
Engine
Operation.		 165
11.3.4
Cooling
Circuit		 165
11.4 Operation
Monitoring
in
Marine
Diesel
Engines.		 166
11.5 Development
Tendencies.		 166
11.5.1
Conventional
and
New
Materials		 166
11.5.2
Use
of
Diesel-Electric
Systems.		 168
11.5.3
Improving
Operation.		 168
11.6 Summary
and
Recommendations:
Development
of
Marine
Engine
Technology		 170
References 171
12 Type Approval
and
Type
Certification		 173
12.1 Tests
of
Vehicles		 173
12.1.1
International
and
National
Legislation.		 174
12.1.2
Cars,
Light
and
Medium
Heavy
Duty
Trucks.		 174

xiv Contents

12.1.3 Heavy
Duty
Vehicles		 177
12.2 Tests of
Airplanes		 178
12.2.1 Emission
Requirements		 178
12.2.2 Sampling,
Sample
Transfer,
Instrumentation
and
Measurement
Technology		 180
12.2.3 JAR-E
and
CS-E
for
the
Certification
of
Engines		 180
12.2.4 Certification
of
Auxiliary
Power
Units		 182
12.3 Tests of
Ships		 183
12.3.1 Classification
and
Judgment.		 183
12.3.2 International
Environmental
Regulations		 184
12.3.3 Sulphur
Concentration.		 184
12.3.4 Nitrogen
Oxide
Concentration		 185
12.4 Summary and
Recommendations:
International
Type
Approval
and
Type		 Certification 186
12.4.1 Vehicle
Type
Approval		 186
12.4.2 Airplane
Type
Certification		 187
12.4.3 Ship
Certification		 187
References 188
13 Inspection
and		 Maintenance 191
13.1 Inspection and
Maintenance
in
Road
Transportation		 192
13.1.1 OBD
in
Vehicles
with
Spark
Ignition
Engine.		 193
13.1.2 OBD
in
Vehicles
with
Self
Ignition
Engine		 195
13.2 Inspection and
Maintenance
in
Aviation		 198
13.2.1 Inspection
of
Airplanes		 198
13.2.2 Maintenance
of
Airplanes		 199
13.2.3 Maintenance
Steering
Group		 199
13.3 Engine Deteriorations 200
13.4 Commander's Responsibility 201
13.5 Inspection and
Maintenance
in
Ships		 201
13.5.1 Maintenance
Concepts.		 202
13.5.2 Crew's
Responsibility		 203
13.6 Summary and
Recommendations:
Inspection
and Maintenance 204
13.6.1 Vehicle
Technology		 205
13.6.2 Airplane
Technology.		 205
13.6.3 Ship
Technology		 205
References 206
14 Navigation 209
14.1 Road Transportation 209
14.1.1 Ecologic
Strategy
of
Navigation		 211
14.1.2 Foresighted
Driving		 211
14.1.3 Convoy
Travel
with
Heavy-Duty
Vehicles.		 212

Contents xv

14.2 Navigation in
Aviation		 213
14.2.1 Airports
and
Aircraft
Operators		 213
14.2.2 Information
for
Civil
Aviation
Personnel.		 214
14.2.3 Air
Traffic
Control
Services.		 214
14.2.4 Weather
Conditions
and
Airport
Operating
Minima		 216
14.2.5 Flight
Rules		 216
14.2.6 Optimum
Climbing
Path
and
Flight
Profile
After
Takeoff		 217
14.2.7 Descent
and
Approach
Path
Optimizing		 218
14.2.8 Fuel
Saving
by
Improved
Airspace
Coordination
and
Air
Traffic
Organization		 218
14.3 Ship Navigation 219
14.3.1 Shipboard
Routing
Assistance		 219
14.3.2 Ship
Distress
and
Safety
Communications		 220
14.3.3 Meteorological
and
Oceanographic
Coordinator
and
Supporting
Service		 221
14.3.4 Broadcast
for
Navigation		 221
14.3.5 Reporting
Environmental
Damaging
Incidents
at
Sea		 222
14.4 Summary and
Recommendations:
Impact
of
Navigation
on
Fuel		 Consumption
and
Emissions.		 222
14.4.1 Vehicle
Navigation		 222
14.4.2 Airplane
Navigation		 223
14.4.3 Ship
Navigation		 224
References 224
15 Climate and Environmental
Protection		 227
15.1 Transportation
Emissions.		 227
15.2 Interaction Between
Climate
and
Economy		 229
15.3 Climate Protection
in
Road
Transport		 229
15.3.1 Legislation
and
Regulations		 230
15.3.2 Comparison
of
Regulations		 230
15.4 Climate Impact
of
Aviation		 231
15.4.1 Trading
with
CO2
Emissions
in
Aviation.		 232
15.4.2 Impact
of
Climate
Change
on
Air
Traffic		 234
15.5 Climate Impact
of
Shipping		 235
15.5.1 Large
Two-Stroke
Marine
Diesel
Engines		 236
15.5.2 Average
Auxiliary
Engines		 237
15.6 Recycling and
Climate
Balance
of
Transportation		 238
15.6.1 Recycling
of
Vehicles		 238
15.6.2 Recycling
of
Airplanes		 239
15.6.3 Recycling
of
Ships		 240

xvi Contents

15.7 Summary
and
Recommendations:
Climate
Protection
in
Transportation		 240
15.7.1
Vehicle
Technology		 241
15.7.2
Aviation
Technology.		 241
15.7.3
Maritime
Technology		 242
References 242
16 Transportation
Costs		 245
16.1 Tendencies
of
Fuel
Supply		 245
16.2 Prices
of
Fuels		 245
16.3 Prices
of
Measurement
Technology		 247
16.4 Cost
of
Road
Mobility		 248
16.4.1
Improvements
in
Low-Cost
Car
Models		 249
16.4.2
Safety
and
Health		 249
16.4.3
Environment
and
Climate
Protection.		 250
16.5 Costs
in
Aviation		 251
16.5.1
Development
Phases		 251
16.5.2
Purchase
Price		 251
16.5.3
Operating
Costs		 251
16.6 Costs
in
Shipping		 253
16.6.1
Improved
Efficiency		 255
16.6.2
Early
Scrapping		 255
16.6.3
Costs
and
Tendencies
of
Natural
Gas
Application
as
a
Marine
Fuel		 255
16.7 Cost
Saving
in
Transportation		 257
16.7.1
Vehicle
Technology		 257
16.7.2
Aviation
Technology.		 257
16.7.3
Ship
Technology		 258
16.8 Summary
and
Recommendations:
Costs
in
Road
Transport,
Aviation,
and
Maritime
Shipping		 258
16.8.1
Costs
in
Road
Transport		 259
16.8.2
Costs
in
Aviation		 259
16.8.3
Costs
in
Maritime
Shipping		 260
References 260
17 Future Transportation
Systems.		 263
17.1 Future
Trends
of
Road
Vehicle
Technology.		 263
17.1.1
Near
Future
Phases
of
Development		 264
17.1.2
Far
Future
Phases
of
Development		 268
17.2 Future
Trends
in
Aviation
Technology		 276
17.2.1
Near
Future
Phases
of
Development		 277
17.2.2
Far
Future
Phases
of
Development		 279
Contents xvii
17.3 Future
Trends
in
Ship
Technology		 284
17.3.1
Near
Future
Phases
of
Development		 285
17.3.2
Far
Future
Phases
of
Development		 288
17.4 Summary
and
Recommendations:
Future
Environment
Friendly
Transportation		 291
17.4.1
Future
Vehicle
Technology		 291
17.4.2
Future
Aviation
Technology.		 292
17.4.3
Future
Ship
Technology		 293
References 294
18 Interaction
Between
Future
Transportation
Technology
and Future
Fuel
Supply		 297
18.1 Time
Dependency.		 297
18.2 Saving
Fuel		 297
18.3 Summary
and
Recommendations:
Scenarios
of
Future
Transportation		 300
References 301
Appendix A:
Applied
Units
and
Conversions		 303
About the Author 309
Index 311

Abbreviations

AAC Alaska Marine Vessel Visible Emission Standard ACNS Airborne computer-based navigation system

AFDS Autopilot Flight Director System

ADC Analogue-digital converter AFL Airplane flight log

AFP Alloy ferritic-pearlitic

AIP Aeronautical information publication AIS Automatic identification system

ALU Arithmetic logic unit

AMOC Area Meteorological and Oceanographic Coordinator

APU Auxiliary power unit

ARO Air Traffic Services Reporting Office ASTM American Society for Testing and Material

AT Auto throttle system ATC Air traffic control ATM Air traffic management ATS Air traffic service

BEV Battery driven electric motor vehicle

BPR Bypass pressure ratio

BSFC Best specific fuel consumption

BTL Biomass to liquid CAA Civil Aviation Authority CAC Charging air cooling CAD Computer-aided dispatch

CAEP Committee on Aviation Environmental Protection

CAFÉ Corporate average fuel economy

CAI Controlled auto ignition

CAN Controller area network

CARB Californian Air Resources Board

CCNR Central Commission for Navigation on the Rhine

CDA Continuous descent approach

xx Abbreviations

CDU Control display unit CDL Configuration deviation list CEV Combustion engine vehicle CFC Carbon fibre composite CFD Computational fluid dynamics CLD Chemo luminescence detector

CM Condition monitoring CN Cetane number

CNG Compressed natural gas

CNS Communication, navigation and surveillance

COP Compliance of production CPU Central Processor Unit CRT Cathode ray tube CSR Common structural rules CVS Constant volume sampling DAC Digital-analogue converter DGPS Digital global positioning system DME Distance measuring equipment DOC Direct operation cost

DPNR Diesel particulate NOx reduction

DWT Deadweight tonnage

EASA European Aviation Safety Agency

EC European Commission ECAC European Civil Aviation Conference, Regional body of ICAO

for European regions

ECD Electronic chart display

ECDIS Electronic chart display and information system

EDC Electronic diesel control

EEC European Economic Community EEDI Energy efficiency design index EEP Engine enhancement package

EEPROM Electrically erasable programmable read-only memory

EFIS Electronic flight instrument system

EGAS Electronic accelerator gas EGT Exhaust gas temperature

EPROM Electronic programmable read only memory ERAA European Regions Airline Association

ETC Exhaust turbo charger ETP Equal-time point

ETSO European technical standard orders

ETOPS Extended-range twin-engine operation performance standards

EU-OPS European operation performance standard

FAA Federal Aviation Administration FADEC Full authority digital engine control

FAME Fatty acid methyl ester

Abbreviations xxi

FAR Federal aviation regulation

FBP Final boiling point

FC Fuel cell

FCC Flight Control Computer

FCY Flight cycles

FID Flame ionisation detector FEW Fuel–water emulsion FHEV Full hybrid engine vehicles

FM Field monitoring

FMS Flight management system FTIR Fourier transformation infra red FTP Federal test procedure

FAB Functional airspace block

GAMA General Aviation Manufacturers Association

GC Green card

GDP Gross Domestic Product GHG Green house gases

GMDSS Global maritime distress and safety system

GPS Global positioning system

GPU Ground power unit GSM Global system for mobile telecommunication

GT Gross tonnage GTL Gas to liquid

GVWR Gross vehicle weight rating

HCCI Homogenously charged compression ignition

HCO Heavy cycle oil

HDDE Heavy commercial diesel engine HDT Heavy commercial truck HDV Heavy commercial vehicle HDC Highway driving cycle

HFO Heavy fuel oil

HSLA High strength low alloy HWFET Highway fuel economy cycle

IACS International Association of Classification Societies

IATA International Air Transport Association IC International convention

ICAO International Civil Aviation Organization ICCT International Council on Clean Transportation ICT Information and Communication Technology

IFO Intermediate fuel oil IFR Instrument flight rules

ILO International Labour Organization

IM Inspection and maintenance

IMC Instrument meteorological condition IMO International Maritime Organization

xxii Abbreviations

IOSA International operation safety audit

IRS Inertial reference system

ISA International standard atmosphere ISM International Safety Management JAA Joint Airworthiness Authority

JAA-OPS Joint Airworthiness Authority-Operation Performance Standard

JAR Joint airworthiness requirement JTSO Joint technical standard order LCD Liquid crystal display LDT Light duty truck LDV Light duty vehicle LF Low frequency LNG Liquid natural gas

MARPOL International convention for the prevention of maritime

pollution from ships

MDF Marine destillate fuel MDO Marine diesel oil MEL Minimum equipment list

MEPC Marine Environment Protection Committee

MF Medium frequency MGO Marine gas oil

MMI Man–machine interface MOT Ministry of Transport MP Maintenance Program MSC Maritime Safety Committee MSG Maintenance Steering Group MSI Maritime safety information MTOW Maximum takeoff weight NAA National aviation authority NEDC New European Driving Cycle

NOTAM Notices to airman OAT Outside air temperature OBD On-Board diagnosis OBM On-Board measurement OC On condition

OCA Oceanic control area

OFCA Operational fuel consumption analysis

OPR Overall pressure ratio PCM Phase changing material PHEV Plug-in hybrid engine vehicle

PO Peak oil

PROM Electronic Programmable Read-Only Memory

RAM Random access memory RBM Risk-based Maintenance

RCM Reliability centered maintenance

Abbreviations xxiii

RMF Residual marine fuel

RNP Required navigation performance

SAFC Solid acid fuel cell SC Start control cycle

SCR Selective catalytic reduction

SD Self Diagnosis SFC Specific fuel consumption

SI International System of Units (Système International d'Unités)

SN Smoke number SMS Short message service SOLAS Safety of life at sea

SRAS Shipboard routing assistance system

TA Type approval TC Type certification TMC Traffic message channel

TEU Twenty equivalent units (20 feet container)

Tier Emission Standard in the USA

TOC Top of climb

TSFC Thrust specific fuel consumption

TSO Technical standing order TST Total seaborne trade TST Type sample test

TÜV Technischer Überwachungsverein UDDS Urban dynamometer driving schedule

UHB Ultra high bypass

UNFCCC United Nations Framework Connection on Climate Change

VFR Visual flight rules

VHF Very high frequency VLA Very large airplane VTG Variable turbine geometry WAFS World area forecast system WHSC World harmonized stationary cycle WHTC World harmonized transient cycle

Chapter 1 Basics of Fuel Consumption and Exhaust Gas Emissions

The central topics of the book are fuel consumption and exhaust gas emission saving technologies, monitoring possibilities, infrastructure impacts, administrative and legislative options, and financial and social conditions in transportation.

This book has five main chapters (see Fig. 1.1).

All means of transport consume fuel and emit waste products into the air. The fundamentals of recent technology are depicted in [1]. This book deals with fuel consumption and exhaust gas emissions from internal combustion and jet engines in motor vehicles, ships, and airplanes, and does not survey railroads, and it furthermore considers unburned hydrocarbons, carbon monoxide, nitrogen monoxide, nitrogen dioxide, particles and carbon dioxide, and does not include other pollutants and climate gases.

Regarding the complexity of transport, the most important potentials for fuel savings are in the technology of vehicles, airplanes and ships, in the organization of transportation systems and in the optimization of environmental conditions, which is the main guide for consideration in this book (see Fig. 1.2).

1.1 Comparison of Fuel Consumption and Emissions in Transportation

Fuel consumption of vehicles can be expressed using the metric unit system in terms of consumed fuel per passenger kilometer and passenger mile or per weight of transported cargo:

• Fuel volume or fuel mass per passenger-kilometers in l (passenger km)-1 or kg (passenger kg)-1

1

Fig. 1.1 Structure of the book

  • Fuel volume or fuel mass per freight mass and distance, or freight volume and distance in l (kg km)-1 and l (m3 km)-1 , or kg (kg km)-1 and kg (m3 km)-1 ; and
  • Fuel volume or fuel mass per engine performance or engine thrust as Specific Fuel Consumption (SFC) in ml (kNh)-1 and ml (kWh)-1 or g (kNh)-1 and g (kWh)-1 .

Unlike the metric system (International System of Units (SI) or Système International d'Unités), the imperial measurement system gives details on attainable distance per volume of fuel, i.e., mile per gallon or mpg consumed. In the USA, and in the UK in the past (Imperial Unit), the energy intensity of travel was often expressed in units of BTU per mile, i.e., BTU mi-1 . The tables and remarks in this text systematically contain all units [2].

In the metric system, the amount of exhaust gases can be expressed in g km-1 or oz mi-1 in road transportation, and in g nmi-1 or oz nmi-1 in shipping and in aviation. The particles can be characterized by the average diameter in mm or in inches, and the number of the emitted particles without physical units.

Fig. 1.2 Main routes of fuel and emission savings in traffic

Fuel consumption and emissions are measured at the test bench in control cycles. The consumption quotas from individual cycles are partly different in the road, ship and airplane technologies and therefore not directly comparable. CO2 emissions can be derived from the fuel consumption.

Table 1.1 presents a comparison of the fuel consumption of different means of transportation.

1.2 Principle of Continuous Controlling Combustion Process

Deterioration and wear and tear cause increased fuel consumption and exhaust gas emissions. Monitoring deterioration is an important way to detect errors in time.

On-Board Diagnosis (OBD) was introduced in vehicle technology as the first continuous inspection measure in operation [9]. OBD makes it possible to control exceeding combustion and emission limiting values with sensor signals of combustion and emission relevant elements in vehicles. In principle, the diagnosis, i.e., the indirect control of combustion and exhaust gas emission technology has been applied to airplanes and ships in a very similar way but with other names. It is the current state of the art in all means of transportation.

Direct control of the chemical composition of burning products with micro sensors in the combustion chamber and in the exhaust gas system is only partly state of the art although it could precisely characterize the combustion and the exhaust gas after treatment process. In the future, if appropriate sensors are suitable, a combination of OBD and On-Board Measurement (OBM) technology will be able to further improve fuel combustion and exhaust gas emission savings [10].

The next stage of direct measurement is the complex use of ''Self Diagnosis'' (SD) of engines in vehicles, airplanes and ships. SD does not only record when limit values are exceeded, but also all fuel consumption and emission relevant phases of operation which characterize the change of operation parameters during the whole life cycle. Real ''may be wrong'' fuel consumption and exhaust gas

Means of
transportation		 Local passenger traffic Overland passenger
traffic		 Freight transportation
Fuel consumption Fuel consumption Fuel consumption
kJ
(t km)-1		 (BTU
(sht mi)-1
)		 kJ
(t km)-1		 (BTU
(sht mi)-1
)		 kJ
(t km)-1		 (BTU
(sht mi)-1
)
Passenger cara 2,595.7 (3,597.6) 2,633.1 (3,619.5) –
Long distance
busb		 – 811.3 (1,124.5)
Public service bus 1,192.4 (1,652.7) – –
Railway – 757.6 (1,050.0) 386.9 (536.2)
Airplanec – 3,116.8 (4,319.9) 4,503.1 (6,241.3)
Light duty vehicle – – 1,434.1 (1,987.7)
HDV (40 t,
88.2 lb))		 – – 1,176.6 (1,630.8)
Inland shipd – 865.0 (1,198.9)
Ferry – 1,678.1 (2,325.8)
Fast ferrye 2,366.4 (3,279.8)
Seagoing shipf – – 564.2 (782.0)

Table 1.1 Comparison of the fuel consumption of different means of transportation in metric energy units per tons and kilometers, and in british thermal units per short tons and miles

emission data can be related to the pre-defined norms, which generally describe the ''may be proper'' operation, usually measured against the starting phase of the life cycle. Similar optimal conditions of operation can also be attained after general inspections and maintenance measures.

Comparison of currently measured data with stored parameters in operation can lead to the discovery of even smaller deteriorations (see Fig. 1.3).

The preconditions for the Self Diagnosis technology are micro sensors of high quality and durability, and micro controllers of high storage capacity and high operation speed.

1.3 Legislation Frame Conditions

The European Union Directives 1998/69/EC [11] and 1999/96/EC [12] contained an important and ground breaking formulation, which stated that monitoring is not only possible for individual components, but also for the composition of the

a Mid-sized car with four-stroke self-ignition engine with turbocharger and Common Rail [3] b Simple deck with 44 seats and a fuel consumption of 25 l 9 100 km-1 , i.e.,

40.2 l 9 100 mi-1 or 9.4 mpg (US) and 11.3 mpg (UK) [4] c Mid-range single aisle airplane with two turbofan engines [5] d Small tugboat [6] e Water jet propulsion, speed 30–37 knots, SFC 200–212 g (kWh)-1 , i.e., 2.10–2.23 9 10-3 oz BTU-1 [7] f Large container ship [8]

Fig. 1.3 Principles of Self Diagnosis in transportation

exhaust gas through the use of an appropriate measuring technique as a supplement to the pure OBD for road transportation. The direct survey of combustion and other emission relevant processes could be also used in ship and airplane technology. However, OBM should not be considered a substitute for diagnostics, i.e., for the OBD technology, but can be viewed as an additional element to the diagnosis.

With respect to emissions from heavy duty vehicles (Euro 6), the European Commission has required the application of Portable Emissions Measurement Systems (PEMS) in the Commission Regulation (EU) No 582/2011 [13]. The on-board monitoring of NOx and PM emissions to improve the emission related maintenance is the main aspect of regulation.

1.3.1 Lack of Micro Sensors and Micro Controller Systems

The current limitation of the practical use of Self Diagnosis systems is the lack of selective, durable and precisely functioning sensor systems, and the lack of fitted micro controller systems for the long time recording and analyzing sensor signals on-board.

Micro sensors, which can be successfully implemented in air measurement technology, break down in emission measurement systems, e.g., in the exhaust gas after treatment system of road vehicles or ships. Figure 1.4 presents some examples of sensors for air quality monitoring [14].

Fig. 1.4 Micro devices for air measurement technology

Current micro measuring sensors can only limitedly operate in the combustion chamber and the exhaust gas system of cars, airplanes and ships. One exception is the electrochemical technique which uses zirconium dioxide technology for the analysis of oxygen concentration in the exhaust gas.

1.3.2 Variability of Real Travel Conditions

There is a meaningful difference between fuel consumption and exhaust gas emissions measured at the test bench and in the real travel, flight, and ship navigation (see Fig. 1.5).

Accelerating and braking phases are exactly defined at test benches. According to them, the measured signals of exhaust gas concentrations are unified and always comparable with each other. In opposite to these defined time distributions of signals at test benches, real concentrations of emissions are unregulated and depend on load, journey, and environmental conditions.

Concentrations and mass flows measured in real traveling, flying, and shipping must always be related to internal engine and external journey parameters. The systematic comparison of ''normalized'' present data with stored ''basic'' data is the fundamental principle of the Self Diagnosis technology.

  • 1. tropical and arctic regions 2. mountains and shallow lands
  • 4. regions with high and low wind potentials 3. rain forests and deserts
  • 6. low and high level of load 5. start and driving hill up and hill down

Fig. 1.5 Comparison of test bench conditions with dynamic control of deteriorations with the help of Self Diagnosis

Fig. 1.6 Comparison of operation emissions to test bench emissions with the Artificial Neuronal Network (ANN)

1.4 Conversion of Real Operation Emissions to Test Bench Emissions

The key problem of Self Diagnosis is the conversion of real operation emissions to test bench emissions. In practice, environmental conditions are very variable and must be related to the nominal conditions at the test bench [15]. A possible conversion can be obtained through the use of mathematical methods on-board, if future micro controller technology has very high operation speed and storage capacity (see Fig. 1.6).

Similarly to the sensor technology, recent on-board micro controller systems are only partly able to fulfill all of these high quality conditions. Besides hardware also new, on-board software systems are needed to transfer and compare real data with stored data [16].

1.5 Specific Characteristics of Vehicles', Airplanes' and Ships' Emissions

Experiences show that only a few time intervals of real drive, flight, and ship navigation can be compared with original phases.

Fig. 1.7 Unburned raw hydrocarbon concentration in a mid-size car without and with errors

Spark ignition engine emits larger amounts of unburned hydrocarbons and carbon monoxide upstream to the catalyst which can be precisely recorded in the automatic cold starting phase (see Fig. 1.7).

Peaks in cars have short time intervals between 0.1 and 1.0 s.

Exhaust gas emissions of airplanes' and ships' engines are significantly different from car engine emissions. However, despite all of the differences in emission characteristics, the basic functions are the same. The composition of combustion products generally depends on the type and the load of the engine, and the operating conditions.

On airplanes, micro sensors for burning products could be installed in the combustion chamber, similar to the temperature and pressure sensors. Micro measuring systems could compare the signals of individual jet engines measured against each other. On the basis of these variable and multistage comparisons, even small changes within the engines can be discovered over time and compensated with fitted correction measures. Micro emission measuring systems can combine burning parameters with all other sensor signals of the airplane and consider all phases of flight, including the speed, altitude, and maneuvering of the airplane.

On ships, micro sensors must be protected against the raw environment conditions on oceans. Salt water, high humidity, and changing exhaust gas conditions require an accordingly protected case and resistance against corrosion. The most important parameters in ship exhaust gas are NOx, SOx, and PM. Changes over time are slow and signals are usually without fast occurring peaks.

1.6 Summary and Recommendations: Basics of Intelligent Monitoring of Fuel Consumption and Emissions

Two European Directives EC 98/69 and EC 99/96 form the basis of intelligent, direct control of combustion and exhaust gas after treatment technology. Both Directives contain a passage concerning direct measurement technology in passenger cars and light duty vehicles.

Fuel consumption and exhaust gas emission quotas of several driving cycles are different and not directly comparable with each other. Existing comparisons merely operate within average conditions. Direct monitoring opens the way to direct and quasi continuous measuring fuel consumption and exhaust gas emissions. Self Diagnosis uses the history of changes in engine operation and compares original data with real data measured in daily traffic.

However, this technology is still under development. The first problem is the lack of high quality micro sensors. The second problem is the price of sensors. Recent systems are still too expensive for mass production and too sensitive to raw conditions in the environment.

Currently, deteriorations are measured at test benches under artificial conditions. Certification prefers artificial measures. Exceeding limiting values can be tested through changing new and optimally operated elements with artificially worn and deteriorated elements in the fuel consumption and the related exhaust gas systems. Both cases ''may be proper'' and ''may be wrong'' operations are measured in driving, flying, or shipping navigation cycles on the test bench. The fuel consumption and parallel to it, the exhaust gas measuring procedure on the test bench, have to be repeated multiple times, with both ''new'' and changed ''old'' elements. Results are only partially related to the real fuel consumption and exhaust gas emissions.

Although development has been accelerating in the last years, it is expected that the evolution of intelligent Self Diagnosis technology will be gradual and slow due to complex technological problems.

References

References 11

  1. Bunkerworld Forums (2006). http://www.bunkerworld.com/forum/Ask+Dr.+Vis/thread\_22/
  • 9. Performing onboard diagnostic systems checks as part of vehicle inspection and maintenance program. EPA 420-R-01-015. June 2001
  • 10. Friedrich A, Tappe M, Garms S, Palocz-Andresen M, Schroll S (1998) On-Board-Diagnose (OBD) und On-Board-Messung (OBM) im Kraftfahrzeug. WLB Wasser, Luft und Boden. 7–8, pp 46–48
  • 11. Directive 98/69/EC of the European Parliament and of the Council of 13 October 1998 relating to measures to be taken against air pollution by emissions from motor vehicles and amending Council Directive 70/220/EEC
  • 12. Directive 99/96/EC of the European Parliament and of the Council on the approximation of the laws of the member state relating to measures to be taken against the emission of gaseous and particulate pollutants from compression ignition engines for use in vehicles, and the emission of gaseous pollutants from positive ignition engines fuelled with natural gas or liquefied petroleum gas for use in vehicles and amending Council Directive 88/77/EEC
  • 13. Commission Regulation (EU) No 582/2011 of 25 May 2011 implementing and amending Regulation (EC) No 592/2009 of the European Parliament and of the Council with respect to emissions from heavy duty vehicles (Euro VI) and amending Annexes I and III to Directive 2007/46/EC of the European Parliament and of the Council
  • 14. Dräger X-am 7000. Product catalogues of sensors 2007. http://www.draeger-safety.com
  • 15. Development of Fuzzy Logic and Neural Network Control and Advanced Emissions Modeling for Parallel Hybrid Vehicles. CAR Dec. 2003, NREL/SR-540-32919 Ohio University http:// www.scribd.com/doc/61640893/67/
  • 16. Eckhardt U, Palocz-Andresen M, Oetjen PD, Weber T (2005) Determination of on road vehicle issue characteristics using artificial neuronal networks. Measuring tm technically, pp 524–531

Chapter 2 Fuels in Transportation

In 1900 there were no gas stations—blacksmiths and pharmacists sold the fuel. People first used petrol for lighting and later to lubricate machine tools. At the end of the 19th century, boilers in factories and in ships began to use oil instead of coal [1]. Since this time the consumption of oil, coal and natural gas has been continuously growing.

Figure 2.1 presents the development of fossil fuel consumption and CO2 emissions [2].

2.1 Classification of Types of Fuels

There is an increasing variety of fuels, which are presented in Fig. 2.2.

The heating value of liquid fuels is relatively equal per mass unit. It is about 11.0– 12.0 kWh kg-1 (17,017–18,564 BTU lb-1 ), which is equal on average to 39,574– 43,172 kJ kg-1 . Gasoline has a volume-specific heating value of 8.8 kWh l-1 (113,660 BTU gal-1 (US) or 136,512 BTU gal-1 (UK)), i.e., 31,680 kJ l-1 at a density of 0.762. Diesel fuel has a volume-specific heating value of 10.0 kWh l-1 (129,163 BTU gal-1 (US)), i.e., 36,000 kJ l-1 , because of its higher density (0.835) [3].

Components of alternative fuels containing oxygen, such as biological ethanol (29,700 kJ kg-1 , i.e., 12,771 BTU lb-1 or 155,132 BTU gal-1 (UK), ether, and fatty acid methyl ester have less heating value than pure hydrocarbons, since the oxygen bound in the molecule does not take part in the burning. Kerosene has a mass-specific heating value of 38,000 kJ kg-1 , i.e., 16,340 BTU lb-1 , and heavy fuel oil approximately 41,200 kJ kg-1 or 17,716 BTU lb-1 . The density of kerosene is similar to diesel fuel. Heavy fuel oil has a higher density, depending on the quality [4].

Fig. 2.1 Global consumption of fossil fuels and CO2 emissions per year

Fig. 2.2 Most important types of fuels

The different types of fuels have varying physical and chemical properties (see Table 2.1 [5]).

The different physical and chemical properties lead to changes in containing, pumping, spraying, and burning characteristics.

2.2 Road Transport Fuels

Gasoline, diesel, and environmentally friendly vehicle fuels are used in road transport in the largest quantity.

Substance Density Melting point Boiling point
g cm-3 (oz in-3
)		 C (F) C (F)
Gasoline/petrol 0.72–0.75 0.42–0.43 -50 to -30 -58 to -22 25–210 77–410
Diesel 0.81–0.85 0.47–0.49 -30 -22 150–360 302–680
Methanol 0.79 0.46 -98 -145 65 149
Ethanol 0.79 0.46 -117 -179 78.5 173
Fuel oil &0.83 &0.48 -10 14 [175 [347
Flax oil 0.93 0.54 -15 5 316 601
Petroleum 0.76–0.86 0.44–0.50 -70 -94 [150 [302
Lubrication oil 0.91 0.53 ±0 32 300 572
Silicone oil 0.76–0.98 0.44–0.57 – – – –
Water 1.00 0.58 ±0 32 100 212

Table 2.1 Physical properties of liquids

2.2.1 Gasoline

Different national and regional norms fix the minimum requirements of gasoline (term in the USA) or petrol (term in the UK) or Otto fuel (term in other parts of Europe). In Europe, the requirements are laid out in the norm EN 228 [6].

The main characteristics of gasoline are contained in Table 2.2.

2.2.1.1 Environmental Friendly Gasoline and Additives

Environmentally friendly products ensure optimal burning characteristics and pollutant emissions [7]. They contain a low concentration of aromatic hydrocarbons, benzene, and sulfur and have low vapor pressure as well as a low boiling end point.

Additives in environmentally friendly fuels are required by law in the USA to protect injection systems [8].

2.2.1.2 Reference Fuels

Directives require reference fuels for driving certification in Type approvals (TAs). Emission limits depending on the fuel type are strictly regulated in all regions of the world.

The Euro 5 and Euro 6 norms are part of the EU committee overseeing the implementation (see Table 2.3 [9]).

The American Society for Testing and Materials D439 (ASTM) specifies the norms for gasoline in the USA [10]. Table 2.4 presents the gasoline reference fuel in the USA for vehicles with a spark ignition engine.

Table 2.2 Characteristics of petrol

Parameters Physical and chemical characteristics
Type of fuel The most important types in road mobility are normal and super fuels. Super
fuels have a lower knocking characteristic in high compression engines
than normal fuels. In addition, the volatility is different in normal and
super fuels which influence summer and winter applications in regions
Density In Europe, the permitted density range for gasoline fuels is limited to
720–775 kg m-3 (44.94–48.44
lb ft-3
) in the EN 228. Super fuels have
a higher density than normal fuels and also an insignificantly higher
heating value because of the generally higher concentration of aromatic
hydrocarbons
Octane number The octane number indicates the anti-knocking characteristic of petrol. If
the octane number is higher, there are more anti-knocking substances in
the fuel. The octane number can be characterized by the research octane
number (RON) and the motor octane number (MON)
Additives Additions of components containing oxygen, e.g., methanol, ethanol, methyl
tertiary butyl ether beneficially increase the octane number, but can lead
to other difficulties. Problems can arise because alcohols increase the
volatility and can attack the internal material of tubes, pipes, and tanks
Volatility To ensure optimal road performance, volatile components must provide an
optimal cold start, but high volatility must not lead to problems either in
the hot start or in the ''vapor lock'' at higher temperatures. In addition,
the evaporation losses must be kept low in order to protect the
environment
Vapor pressure In Europe, the vapor pressure of fuels is measured at 38C (100F)
according to EN 13016-1. Gas bubbles at temperatures between 80 and
100C (176 and 212F) can lead to disturbances while driving.
Therefore, the steam pressure is limited in all specifications, e.g., in
Germany in the summer at a maximum of 60 kPa (1,253.1 lbf ft-2
) and
in the winter at a maximum of 90 kPa (1,879.7 lbf ft-2
)
Sulfur content Sulfur lubricates mechanical parts inside the engine. It burns to SO2
and
produces acids which are dangerous to human health and the
environment. In the future, the sulfur content of fuels must be further
reduced. A worldwide content of less than 10 ppm is desirable
Anti-aging
protective
substances		 Anti-aging protective substances or deactivators increase the storage
stability of fuels through the use of crack components. They prevent the
oxidation of fuels and stop the catalytic influence of metal ions
Water Water must not be contained in the fuel because it can destroy the entire
injection system, starting with the injection valves

2.2.2 Diesel Fuel

Diesel fuels consist of single hydrocarbon components, which boil between 180 and 370C (356 and 698F). They are produced through the gradual distillation of crude oil. The refineries also add conversion products, e.g., crack components to the diesel fuel in increasing volume, which are obtained from heavy oils by splitting the long molecules [11].

Parameter Unit Euro 4 Euro 5 and 6
Octane RON/MON 95/98 95/98
RVPa kPa 56–60 50–60
(tonf ft-2
)		 (0.52–0.56) (0.47–0.56)
Density at 15C kg m-3 748–775 743–756
(lb ft-3
)		 (44.21–45.8) (46.4–47.2)
Distillation at 100C (212F) % vol 50–58 48–60
Distillation at 150C (302F) % vol 83–89 82–90
FBPb C 190–210 190–210
(F) (374–410) (374–410)
Aromatics % vol 29–35 29–35
Olefins % vol B10 3–13
Benzene % vol B1 B1
Oxygen % mass B1 Ethanol only
Sulfur ppm B10 B10
Lead g l-1 B0.005 B0.005
(oz gal-1
)		 6.7 9 10-4 (US) 6.7 9 10-4 (US)
8.0 9 10-4 (UK) 8.0 9 10-4 (UK)
Phosphorus g l-1 B1.3 B1.3
(oz gal-1
)		 0.17 (US) 0.17 (US)
0.21 (UK) 0.21 (UK)
Ethanol % vol – 4.7–5.3

Table 2.3 Unleaded petrol reference fuel in the EU

Similar to gasoline, national norms contain the requirements for diesel oil. In Europe, the norm EN 590 determines the quality of diesel fuel [12].

The main characteristics of diesel fuel are contained in Table 2.5.

In Sweden and in California, environmental friendly diesel fuels are stipulated in tax terms in order to reduce pollutant emissions. They are produced at the end of the distillation process, when the content of aromatic hydrocarbons is reduced and the sulfur content is largely eliminated [13].

However, the use of these fuels can lead to considerable problems because of the low lubrication, which is the main reason for wear of the injection valves. In environmentally friendly diesel fuels, special additives are necessary to avoid damage.

2.2.3 Reference Fuels

Diesel reference fuels are used, just as reference gasoline fuels in spark ignition engines, for the process of the Type approval (TA) of self-ignition engines.

a RVP reid vapor pressure b FBP final boiling point

Table 2.4 Unleaded gasoline reference fuel in the USA
Parameter Unit EPA CARBa
Ambient Cold CO
low octane
number		 Cold CO
high octane
number
Octane (R ? M)/2 93 87 ± 8
RVPb psi
(kPa)		 8–9.2
(55.2–63.4)		 11.5 ± 3 11.5 ± 3 6.7–7.0
(46.8–48.3)
RVP Evap psi
(kPa)		 8.7–9.2
(60–63.4)		 7
(46.3–48.3)
T10 F
(C)		 120–135
(48.9–57.2)		 98–118
(36.6–47.7)		 105–125
(40.5–51.6)		 130–150
(54.4–65.5)
T50 F
(C)		 200–230
(93.2–110)		 178–214
(81.2–101)		 195–225
(90.5–107.1)		 200–210
(93.2–98.8)
T90 F
(C)		 300–325
(148.8–162.6)		 316–346
(157.6–
174.3)		 316–346
(157.6–174.3)		 290–300
(143.2–148.7)
FBP F
(C)		 415
(212.6)		 413
(211.5)		 413
211.5		 390
(198.7)
Aromatics % vol 35 26.4 ± 4 32 ± 4 22–25
Olefins % vol 10 12.5 ± 5 10 ± 5 4–6
Benzene % vol 0.8–1.0
Sulfur ppm 15–80c 15–80c 15–80c 30–40
Lead g gal-1
(g l-1
)		 0.05
(0.013)		 0.01
(0.0026)		 0.01
(0.0026)		 0.01
(0.0026)
Phosphorus g gal-1
(g l-1
)		 0.005
(0.0013)		 0.005
(0.0013)		 0.005
(0.0013)		 0.005
(0.0013)

Table 2.6 presents the main physical and chemical properties of diesel reference fuel [14].

Table 2.7 shows the quality of diesel reference fuels in the USA for vehicles with a self-ignition engine [15].

2.2.4 Products of Natural Gas

The most important fuels made from natural gas are Compressed Natural Gas (CNG) and Liquid Natural Gas (LNG). CNG is predominantly methane. For its use in motor vehicles, CNG must be dried, compressed to a pressure of 250 bar (522,136 lbf ft-2 ), and filled into the motor vehicle's tank. Internal combustion engines must be adapted to be able to use CNG [16].

a Californian Air Resources Board

b RVP for altitude testing: 7.6–8.0 psi or 52–55 kPa

c Road fuel will contain 30 ppm on average and a maximum of 80 ppm

Table 2.5 Main characteristics of diesel fuel

Parameters Physical and chemical characteristics
Cetane number Diesel fuel must ignite after being injected into the hot combustion
chamber with compressed air in the shortest possible time. The ignition
quality can be expressed by the Cetane number (CN). A high CN
number leads to easy ignition
Sediments Sediments of liquid paraffin crystals can cause interruption in the fuel
supply and a blockage of the fuel filter at low temperatures.
Crystallization can start at approximately 0C (32F) or in unfavorable
cases above this point
Flash point The temperature of the flash point describes the point at which a
combustible liquid just passes enough vapor into the air over the liquid
that an ignition source can ignite the air and fuel vapor mixture
Boiling point The boiling point influences the operational characteristics of diesel fuel.
Although boiling points with lower temperatures lead to fuels suitable
for cold temperatures, the Cetane number decreases. In this case, the
lubricating qualities worsen and wear increases for the injection valves
Heating value The heating value of diesel fuel depends on its density. Mixtures with
strongly different densities can lead to fluctuations in the mixture flow
because of the different heating values
Viscosity Too low viscosity leads to leakages in the fuel injection and to
deterioration in performance. On the other hand, too high viscosity
worsens the beam and spray processing. Therefore, the viscosity of
diesel fuel has to be within narrow limits
Hydrodynamic
lubrication		 The hydrodynamic lubrication of diesel fuel influences the physical
characteristics of the fuel mixture. In the EU, EN 590 regulates the
level of lubrication
Sulphur content Sulphur is particularly contained in crack components. The concentration
of sulphur has been lowered in several steps worldwide over the last
few years and is currently 350 mg kg-1
, i.e. 350 ppm in Europe
Additives The bonus of additives for improving the quality of diesel fuel has various
effects. The complete concentration of additives is on average less than
0.1%, so that the physical qualities of the fuel, such as density, viscosity
and boiling point, are not changed

To produce LNG, natural gas has to be liquefied and stored at a temperature of -160C (-256F) and a pressure of 2 bar (4,177 lbf ft-2 ). The production of LNG needs a high energy amount to be liquefied. Safe storage in insulated tanks onboard is more complicated than the storage of CNG in gas pressure tanks [17]. Both CNG and LNG can be burned, emitting less CO2 than conventional fuels because of the greater hydrogen to carbon relationship relative to oil products.

Liquefied Petroleum Gas (LPG) is a mixture whose main components are propane and butane and is produced in the extraction of crude oil as well as in the refinery process. It can be liquefied under high pressure [18]. LPG is more expensive than CNG and available in smaller volumes.

Hydrogen is usually produced from natural gas or other fossil energy sources through a chemical reformation reaction. For its use in vehicles, hydrogen must be stored as a gas in a tank at up to 300 bar (626,580 lbf ft-2 ) or as a liquid in a

Table 2.6 Diesel reference fuels in the EU

Parameter Unit Euro 4 Euro 5 and 6
Cetane 52–54 52–54
Density at 15C kg m-3 833–837 833–837
(59F) (lb ft-3
)		 (52.0–52.2) (52.0–52.2)
Distillation T 50 C C245 C245
(F) (C473) (C473)
Distillation T 95 C 345–350 345–350
(F) (653–662) (653–662)
FBP C B370 B370
(F) (B698) (B698)
Flashpoint C C55 C55
(F) (C131) (C131)
Kinematic Viscosity at 40C m2 s
-1		 (2.2–3.2) 9 10-6 (2.2–3.2) 9 10-6
(104F) (ft2 s
-1
)		 ((23.95–34.37) 9 10-6) ((23.95–34.34) 9 10-6)
Polycyclic aromatics % mass 3.0–6.0 9 10-6 2.0–6.0 9 10-6
Sulfur ppm B10 B10
FAMEa % vol – 4.5–5.5
Oxidation stability g l-1 B0.025 B0.025
(oz gal-1
)		 (B33 9 10-4 (US)) (B33 9 10-4 (US))
(B40 9 10-4 (UK)) (B40 9 10-4 (UK))
Oxidation stability at
110C (230F)		 h – C20

a Fatty acid methyl ester

Table 2.7 Diesel reference fuels in the USA

Parameter Unit EPA/CARB specification
Cetanea F 400–460/400–490
(C) (204–238/204–254)
Distillation T 10 F 470–540/470–560
(C) (243–282/243–293)
T 50 F 560–630/550–610
(C) (293–332/288–321)
T 90 F 560–630/550–610
(C) (293–332/288–321)
FBP F 610–690/580–660
(C) (321–365/304–349)
Flash point F 130/130
(C) (54/54)
Aromatics % vol 27/8–12
Sulfur ppm 7–15
Kinematic Viscosity at 40C (104F) m2 s
-1		 (1.9–3.2) 9 10-6/(1.9–4.1)
9 10-6
(ft2 s
-1
)		 (20.44–34.43) 9 10-6/(20.44–44.11)
9 10-6

a The refinery can choose between the requirements for Cetane number and for aromatics

Designation Diesel fuel
from the refinery		 Synthetic
fuel		 Advantages and disadvantages
Sulfur content
ppm		 10–5,000 0 Low local SO2
emissions and particles
Easier handling in the exhaust gas
after treatment system
Cetane number 40–55 75–80 Low CO, HC, NO and NO2
emissions
Low noise emission levels and smooth
acceleration
Enhanced technical efficiency in the
engine driving characteristics
Density
g cm-3
((lb ft-3
)
Heating value
MJ kg-1
(BTU lb-1
)		 0.82–0.86
(51.2–53.7)
ca. 43
(18.46 9 103
)		 0.78
(48.7)
ca. 44
(18.89 9 103
)		 Slightly increased consumption
on volume basis
Less particle emissions
Slightly smaller consumption on mass basis
Fewer CO2
emissions per kilometer

Table 2.8 Quality criteria of conventional and synthetic fuels in the combustion process

cryogenic tank at a temperature of -253C (-423F). [19]. Preventing leaks in the fuel tank is still an unsolved problem. The innovative storage of hydrogen in metal hydrides or in special carbon modifications is possible, but is rarely used except in submarines [20].

2.2.5 Synthetic Fuels

Synthetic fuels can be produced from natural gas with the Gas to Liquid (GTL) and from coal with the Coal to Liquid (CTL) technology. The final product is identical in both cases. The convertibility of the products between natural gas and charcoal is ensured. With the CTL or GTL technologies the base materials are converted into water–gas (H2 and CO) and later into gasoline and diesel fuel through the use of catalysts with the help of Fischer-Tropsch synthesis. The by-products are liquefied gas and liquid paraffin.

Table 2.8 shows the most important differences in the quality criteria between conventional and synthetic fuels in the combustion process [21].

This technology is mostly used in South Africa. Synthetic fuels are generally colorless and burn cleanly, have a high Cetane number, and are almost sulfur free [22].

2.2.6 Biogenic Fuels

Biogenic fuel, i.e., bio-organic fuel is the name of any plant or animal substances that can be used in combustion engines. They can support not only the fuel production, but also aid the market position of agriculture worldwide, since they increase the income and the employment opportunities of farmers. The aim is to increase the proportion of biogenic fuels up to 10–20% in the worldwide fuel supply [23].

Generally, a distinction can be made between first-, second-, third-, and fourthgeneration biogenic fuels produced by ligneous cellulose or woody sources via new technologies and converted to the end product by the Biomass to Liquid (BTL) technology.

The first generation consists of pressed and chemically improved oil from plants, such as canola or sunflowers.

The second generation is produced from waste biomass, e.g., stalks of wheat, corn, wood, and biomass crops with help of fermentation. Alcohols such as methanol and ethanol are primarily used as alternative fuels for spark ignition engines. Methanol can be produced from raw materials containing carbon such as coal, natural gas, heavy oil, etc. Ethanol is produced from biomass, e.g., sugar cane and grain through fermentation and is used as a fuel or fuel additive in certain countries, e.g., in Brazil and in the USA. Many countries allow up to 53% ethanol to be added to conventional fuel [24].

The third generation is made of gasified organic materials in reactors and by artificial oils produced through the use of catalysts with the help of Fischer-Tropsch synthesis (BTL).

The fourth generation concerns the production of artificial oils from algae. This method is only at the beginning of the research phase.

The physical and chemical characteristics of synthetic and biogenic fuels are presented in Table 2.9 [25].

Lubricity is a term used to describe the ability of compound to reduce friction between moving parts in the engine. Low sulfur fuels have a lower lubricity than high sulfur oils. Biogenic diesel fuels consisting of methyl esters of soybean oil had provide optimal excellent scuffing and adhesive wear resistance which is approximately equal to conventional diesel fuels features [31].

2.2.7 Blended Fuels

Experiences show that the utilization of 10% of alcohol can lead to small changes in the spraying, mixing, and burning properties of fuels. The viscosity as a physical parameter may figure the differences between fossil fuels and alcohols. At 40C (104F), gasoline kinematic viscosity is 0.88–0.71 cSt, diesel fuel viscosity is 1.30–4.10 cSt, and depending on quality alcohol viscosity is 0.74–1.52 cSt [32].

Micro sensors in the exhaust gas system can discover changes under blended fuel operation condition in the combustion process over time and can provide signals for optimal regulation (see Fig. 2.3).

Table 2.9 Use of synthetic and biogenic fuels in road vehicle engine

Biogenic diesel Poor biogenic oils pressed from plants of the first generation must be treated
by transesterification [26]. The reason for the procedure is to improve the
flowing and burning properties of the resinous raw biogenic oils. The end
product is FAME, which is optimally suitable for application in spark and
diesel engines
Alcohols Biomethanol (CH3OH) and bioethanol (CH3CH2OH) can be used in internal
combustion engines in 100% concentration and in blended fuels in
variable concentrations [27]. Although bioethanol has a higher RON than
fossil fuels, which allows increasing the compression ratio in the
combustion chamber, some experiences show early wear in the
combustion engine
Dimethyl ether Dimethyl ether (C2H6O) is a synthetic product with a high Cetane number
which can be burned in a self ignition engine without soot and with
reduced nitric oxide formation [28]. Due to the low density and the high
oxygen content dimethyl ether has a low heating value. In addition, it
requires customization of the injection equipment because of its gaseous
condition
Emulsions Emulsions of water or alcohols in diesel fuel can be optimally used in self
ignition engines [29]. However, alcohols, primarily methanol, are not or
only badly soluble in diesel fuel. Therefore effective emulgators are
needed to stabilize these mixtures. In addition, measures for anti
corrosion protection are also necessary. Emulsions reduce soot and nitric
oxide emissions. But application have only been used in a few fleets up
till now. However, a broad testing of different injection systems could
play an increasing role in the future
Fatty acid methyl
ester		 Fatty acid methyl ester (FAME) can be produced with an alkali-catalyzed
reaction between methanol and vegetable or animal fats which are
obtained from oils and greases, e.g., from canola, soya, sunflowers, etc.
[30]. FAME effectively increases the lubrication of fuels and determines
the quality of the combustion process. However, recent FAME is not
economically competitive with mineral oil-based fuels yet because its
production is too expensive

Fig. 2.3 Measurement of the exhaust gas quality when using blended fuels

A-actuators

2.3 Aviation Fuels

There are two different types of fuels for airplane engines:

  • Hydrogen carbon mixtures, mostly kerosene; and
  • Mixing fuel, e.g., wide cut petroleum ether.

2.3.1 Kerosene

Kerosene has a leading position as a fuel in civil aviation [33]. It has a boiling range of 160–250C (320–482F), is thoroughly cleaned and desulfurized, and consists of 87% carbon and 13% hydrogen. About 5–8% kerosene is generally produced in the distillation process of mineral oil by cracking. Cracking means the splitting up of large hydrocarbon molecules into small ones. A concentration of 0.2–0.4% sulfur in the kerosene is allowed. Aromatic mercaptans provide the typical kerosene smell.

The additive wide cut petroleum ether is available as an alternative jet B fuel for civil aviation. It has a distillation range of 90–250C (194–482F) and consists of up to 65% gasoline such as butane gas, pentane, hexane, and up to 35% cracked kerosene. This composition allows the production of larger quantities at lower prices. The low ignition point of 20C (68F) gives it the classification of the fire class Al. Jet fuel B is solely used in the military because its flash point is lower and it has a lower cold point than Jet fuel A. Civil aviation does not use Jet fuel B for safety reasons [34].

Fuels for gas turbine jet engines must fulfill a number of demands:

  • Low evaporation losses at higher altitudes;
  • High boiling point, because of the danger of becoming too viscous in a cold atmosphere;
  • Low viscosity also at low temperatures for optimal spraying;
  • No more than 15–20% volatile substances to avoid temperatures in the combustion chamber that are too high;
  • High lubrication ability from not too low viscosity to protect fuel valves and pumps; and
  • Near zero concentration of poisonous and corrosive sulfur compounds [35].

2.3.2 Testing Fuel for Engines

International Civil Aviation Organization (ICAO), Annex 16 Appendix 4 contains the specifications for fuel to be used for testing in aircraft turbine engines (see Table 2.10 [36]).

2.3 Aviation Fuels 25

Properties Unit Value
Density at 15C (59F) kg m3 780–820
Distillation temperature
10% boiling point C 155–201
(F) 311–394
Final boiling point C 235–285
(F) 455–545
Heating value of combustion MJ kg-1 42.86–43.50
(BTU lb-1
)		 (18.42–18.70) 9 103
Aromatics % vol 15–23
Naphthalene % vol 1.0–3.5
Smoke point mm 20–28
(in) 0.79–1.10
Hydrogen % mass 13.4–14.1
Sulfur % mass \0.3
Kinematic viscosity at m2
-1
s		 (2.5–6.5) 9 10-6
–20C (-4F) ft2
-1
s		 (27.22–70.76) 9 10-6

Table 2.10 Specifications for fuel to be used in aircraft turbine engines for emission testing

2.3.3 Alternative Fuels to Kerosene in Aviation

Airport infrastructure is optimized for supplying, delivering, and storing kerosene fuels. Any significant changes in fuel type or specification require major modifications of all these elements. This is a serious matter involving major perturbations to the existing system, with significant effort and costs.

Alternative fuels have a significantly lower energy density compared with kerosene. For this reason, airplanes with alternative fuels propulsed jet engines have to be designed with larger fuel tanks. Table 2.11 compares the net heats in the combustion processes of several alternative fuels based on weight and volume [37].

Alternative fuels include alcohols, methane and hydrogen, and methyl esters of vegetable oils as extenders for kerosene. They must be compatible with kerosene and must have sufficient energy density, meet payload and range requirements, and must also be compatible with all metallic and non-metallic parts used in the fuel systems of jet engines, and must achieve adequate lubrication to ensure current safety standards.

The introduction of alternative fuels require new storage and supply systems for current aircraft and airports. The limited availability of new fuels at several airports also requires a new quality of service for aircraft diverted by weather or mechanical problems.

Table 2.12 shows the most important properties of alternative fuels in aviation. The military has pioneered the application of biogenic fuels. At first, the U.S. Air Force introduced using biogenic fuels in 2011. The Federal Aviation Administration (FAA) also wants to allow a 50% addition of biogenic fuel to

Table 2.11 Comparison of alternative fuel's with kerosene's properties

Kind of fuels Density Specific
energy		 Energy
density
Kerosene 1.00 1.00 1.00
Ethanol 1.00 0.50 0.51
Methanol 1.00 0.45 0.46
Liquid methane 0.54 1.16 0.62
Liquid hydrogen 0.09 2.77 0.25

Table 2.12 Most important properties of alternative fuels used in aviation

Substances Physical and chemical characteristics
Ethanol and
methanol		 Ethanol and methanol are liquid fuels that can be pumped and metered in
conventional fuel systems in airplanes [38, 39]. The heating value of
alcohols is lower than that of kerosene. They have a very low flash point
of only 12–18C (53.6–64.4F) and, respectively, a minimum allowed
temperature of 38C (100F). There are also chemical incompatibilities
associated with materials in the fuel system, although these problems
could be remedied with relatively minor changes
Fatty acid methyl
ester		 Adding FAME from vegetable oils, such as soy bean or canola oils to other
biogenic fuels, is starting to be used in aircraft [40]. In this case, additives
and heated supply systems are needed since more than 2% FAME of soy
bean oil raises the freezing point above the specified maximum. Ethanol
blends with jet fuel and adding FAME of vegetable oils to jet fuel results
in less exhaust smoke and particles in high-power conditions, but
increases the emission of CO and HC during idling, along with the
presence of acids and aldehydes. The emissions of NO and NO2
increase
with higher flame temperatures
Cryogenic fuel Aircraft gas turbines can be designed to operate with cryogenic fuels such as
methane or hydrogen [41]. However, conventional fuel systems cannot
handle these fuels. Alternative fuels require additional aircraft fuel
system design, as well as new ground handling and storage systems.
Moreover, cryogenic fuels have to be stored in the fuselage rather than in
the wings to reduce heat transfer. Because methane and hydrogen have
only 65% and 25% of the energy density of jet fuel, fuselages would have
to be considerably larger than current designs, increasing drag and fuel
consumption
Hydrogen For long-range flights, an advantage would be offset by reducing the takeoff
weight because hydrogen and, to a small extent, liquid methane have
higher specific energy than kerosene [42]. Airplanes with ranges over
10,000 km (5,400 nmi) using hydrogen fuel show a reduction of almost
20% in fuel consumption compared to kerosene. Medium- and short
range airplanes flying from 3,200 to 5,500 km (from 1,728 to 2,970 nmi)
have a 17–38% higher consumption of fuel. For methane, there is only a
small benefit for long-range aircraft and a 10–28% higher fuel
consumption for medium- and short-range aircraft

kerosene with certification. One expects full official acceptance of biogenic fuel in aviation in 2012 and 2013. The relevant admittance standards of introduction are ''D 6751'' of the ASTMs and ''Defstan 91-91 for Renewable Fuel'' of the British Authority [43, 44].

2.3 Aviation Fuels 27

Brazil is planning the introduction of biogenic fuel obtained from sugar cane to civil aviation based on the successes in the use of alcohols in road vehicle technology [45].

2.4 Marine Fuels

ISO 8216 and 8217 define the specifications of marine fuels. Marine Distillate Fuels (MDF) such as Marine Gas Oil (MGO) and Marine Diesel Oil (MDO) are on average clean fuels [46]. They are liquid at normal temperatures and have a relatively low density. The fuel can be directly pumped from the storage tank to the supply tank for one day. From here the fuel flows to a lower mixture tank. MDO and MGO fuels are usually used when the vessel is maneuvering [47].

Heavy Fuel Oil (HFO) is the residual part of distillation with a relatively high density. It must be stored in the bunker tank and preheated for pumping to the settling tank. HFO is made suitable for use in marine diesel engines through the addition of certain flammable substances [48].

The physical and chemical properties, such as the viscosity and the density, and the field of application of the Intermediate Fuel Oil (IFO) are between MDF and HFO.

2.4.1 Marine Distillate Fuels

Marine Distillate Fuels are mixtures of different middle distillates from petroleum refining for marine diesel engines which have four qualities for seagoing ships [49]:

  • DMX is a very light gasoil with an excellent cold quality, characterized by the Cloud Point. It is used almost only as an emergency fuel;
  • DMA can also be used as a navy gasoil or Marine Gas Oil (MGO). It is a gasoil of medium density;
  • DMB can be used as a navy diesel oil or a Marine Diesel Oil (MDO). It is a relatively heavy gasoil with parts of vacuum gasoil; and
  • DMC is a fuel consisting of heavy gasoil. Delay oils can also partly be mixed to DMC.

Table 2.13 presents the main parameters of MDF [50].

Parameters Types Temperature Values
C (F)
Kinematic DMX 40 (104) max. 5.5 (5.9 9 10-5
)
viscosity DMA 40 (104) max. 6.0 (6.5 9 10-5
)
cSt (ft2 s
-1
)		 DMB 40 (104) max. 11.0 (11.8 9 10-5
)
DMC 40 (104) max. 14.0 (15.0 9 10-5
)
Density DMX 15 (59) max. 800 (49.94)
kg m-3 (lb
ft-3
)		 DMA 15 (59) max. 890 (55.56)
DMB 15 (59) max. 900 (56.17)
DMC 15 (59) max. 920 (57.44)
Ignition temperature DMX min. 43 (109)
C (F) DMA min. 60 (140)
DMB min. 60 (140)
DMC min. 60 (140)

Table 2.13 Main parameters of Marine Distillate Fuels

2.4.2 Heavy Fuel Oil

HFO is the residual part of the distillation and cracking plants in petroleum refining. The international trade name is Residual Marine Fuel RME, RMG, or RMK.

The parameters of HFO are presented in Table 2.14 [51].

The main ingredients of HFO are alkenes, cycloalkenes, and highly condensed aromatic hydrocarbons, such as asphaltene with about 20–70 carbon atoms per molecule and a boiling range between 300 and 700C (572 and 1,292F). Heterocyclic nitrogen with a nitrogen content of 0.5% by weight and sulfur substances with a sulfur content of 6% by weight and metallic pollutants obtained from oil such as nickel, vanadium, sodium, calcium, and others are concentrated in HFO [52].

The use of HFO is regulated in MARPOL 73/78 Convention, Annex VI, which defines the emissions of sulfur combustion products in certain areas of the ocean. The regulation is important for the environment, because most seagoing ships use HFO for the main engine on the high see with higher sulfur content than permitted in some individual areas. Ships have to switch to environmentally friendly fuels in protected areas [53].

Heavy Cycle Oil or slurry fuel can be contaminated with ''catalyst fines'' when a crushed zeolitic catalyst is used. Micro particles of slurry are often responsible for abrasion in the fuel system and engine. Fines can be eliminated in a separator system or in similar special devices in the processing phase of oil production [54].

Parameters Types Temperature Values
C (F)
Kinematic RME 50 (122) max. 180 (193.7 9 10-5
)
viscosity RMG 50 (122) max. 380 (408.9 9 10-5
)
cSt (ft2 s
-1
)		 RMK 50 (122) max. 700 (735.2 9 10-5
)
Density RME 15 (59) max. 991 (61.87)
kg m-3 (lb
ft-3
)		 RMG 15 (59) max. 991 (61.87)
RMK 15 (59) max. 1 010 (63.05)
Ignition temperature RME min. 60 (140)
C (F) RMG min. 60 (140)
RMK min. 60 (140)

Table 2.14 HFO marine fuel gels at 20C (68F)

2.5 Summary and Recommendations: Fuels in Transportation

More than 95% of the fuels used in transportation are fossil fuels, despite fast growing prices. The aim is to decrease the proportion of fossil fuels in ship navigation to 80% worldwide by 2020.

Fossil fuel consumption can be significantly reduced through the use of pure biogenic fuels of the first generation, like biologically produced diesel and FAME, but the substitution would require substantially higher costs than consuming conventional fuels. Second-generation biogenic fuels such as alcohols promise to be cheaper but are still under development and used only in few countries like Brazil. The third generation uses gasification of organic wastes and synthesis by the Fischer-Tropsch reaction and can be produced more economically than the first two generations. In the long term, the most economic solution is the production of BTL from waste biomass or algae.

Synthetic fuels are produced from coal and natural gas. South Africa (CTL) and Qatar (GTL) are the most important producers [55].

2.5.1 Fuels in Road Transportation

About 90% of fuels are consumed in road transport, only approximately 10% are consumed in other sectors of transportation. From this first amount, about 65% of the total fuel consumption in road transportation is used in passenger car transportation. The EU Commission has the aim of increasing the proportion of biogenic fuels in transportation to 20% by 2020 [56].

The use of biogenic and synthetic fuels is only in the growing phase at present, but they have to gain a higher proportion in the future fuel supply. Great interest is expected in all regions of the world.

Synthetic fuels are produced from coal and natural gas with the Fischer-Tropsch synthesis. Biogenic and synthetic fuels require the same infrastructure and the same engines as commercial petrol and diesel fuels. The combination of individual fuels is possible.

CNG is only a small portion of the fuel used in road transport and its share is growing very slowly. The use of LNG and hydrogen in road transportation as fuel is not yet sure.

2.5.2 Fuels in Aviation

The most important fuel in civil aviation is kerosene. The use of synthetic and biogenic fuels in experimental airplanes is only a small portion of the complete structure. Widespread substitution of kerosene with both new types of fuel is not expected in the near future.

The industry aims to develop and to produce several fuel types as uniformly as possible and to make it easy to switch between fossil and synthetic or biogenic fuels. Theoretically, the first step of adding 50% biogenic and synthetic fuel can be increased to 100%, because chemical additives make alternative fuels very similar to classic kerosene. However, the introduction of alternative fuels will take a long time to happen.

The combustion of hydrogen results in 2.6 times more water vapor than the combustion of jet fuel and would completely eliminate CO2 emissions in aviation. Beside technological diffculties, a disadvantageous aspect is that the utilization of hydrogen requires a new system of logistics, storage, and handling for all aircraft and ground equipment.

2.5.3 Fuels in Maritime Shipping

The most common fuels in ships are MDF and Heavy Fuel Oils. These are conventional fuels and available at a low cost worldwide. Marine diesel engines could theoretically use a broad range of synthetic and biogenic fuels and their mixtures, i.e., flended fuels if engines and containers of the ships were modified.

The application of synthetic and biogenic fuels is not permitted in shipping since their energy content is too low to guarantee the average needed distances at sea, except special sea-going and inland ships. Moreover, the costs of first- and secondgeneration biogenic fuels are much higher than the cost of fossil marine fuels. It is expected that the next generations of biogenic fuel will achieve more advantages in marine transport. Despite all positive developing results, the introduction of biologic and synthetic fuels in ships will happen slowly and will be evolutionary.

LNG is used in LNG carrying tankers, and hydrogen in the fuel cells of submarines. The proportion of non-fossil fuels used in the ship transportation is very small. The first broad ranged applications are expected in ferries, inland ships, and special purpose vessels.

GTL may be a fuel of the near future, if the consumption of demanded energy in the production process can be decreased. Biogas and biogenic fuels are already used in road transportation worldwide. In the shipping they can be introduced in city-ferry routes at first, and then later on short sea routes.

References

Chapter 3 Construction of Transportation Means

Construction is the oldest field of work in the history of transportation means. In the Stone Age, people constructed carriages and ships from wood. Since the Industrial Revolution steel has gained the leading role in construction. Today, there is a broad range of literature and experiences are nearly unlimited for vehicle, airplane, and ship construction. For this reason, the main aspect of the current development in construction is to find the optimal path for decreasing of fuel consumption and exhaust gas emissions.

3.1 Road Vehicles

The first vehicles were powered by steam engines in the eighteenth and nineteenth centuries, and were followed by gasoline and diesel fuel-powered internal combustion engines from the beginning of the twentieth century. The first efforts to save fuel came after the Second World War, but the serious saving of fuel began after the first oil crisis in 1973 [1]. Since then, manufacturers have been developing vehicles that are more and more fuel efficient.

According to the definition of ISO 3833:1977, a motor vehicle is a self-propelled, wheeled transportation mean for operation on roads [2]. Nowadays, there are more than 1 billion road vehicles, including station wagons, and light and heavy duty trucks in the world. More than half of them are cars, but the proportion of commercial vehicles, particularly of heavy duty vehicles (HDVs), is rapidly rising. The USA had the first largest and China had the second largest fleet of motor vehicles with 239.8 and 78 million pieces in 2010 [3].

The amount of fuel used in several countries of the world is quite uneven and depends on the number, the age and the technical quality of vehicles, the average distances traveled, the cost of fuel, and the personal incomes of people. The

Fig. 3.1 Main structural elements of cars

number of inhabitants related to the number of cars and the Gross Domestic Product (GDP) nearly has an inverse relationship [4].

The ratios range from 234 people per car in the Far East to 1.6 people per car in highly developed countries such as those in the EU, Australia, and the USA. The distribution of commercial vehicles is more balanced than the density of cars on the world because supplying people with goods means an important task in all countries. The scope ranges from 55 people per commercial vehicle in Africa to 2.6 citizens per commercial vehicle in the EU, Australia, and Oceania [5].

By 2015, the number of road vehicles will increase to 1.124 billion. Currently fuel consumption is intensively growing in all sectors of road transport. Recent distribution is rapidly changing because of increasing meaning of developing countries. In the next years, Europe will have a portion of 33%, North America 33%, Asia 25%, and other regions 9% [6].

3.1.1 Main Construction Elements of Cars

Automobile body styles are highly variable but the main construction principles are common. The main structural elements of passenger car construction are shown in Fig. 3.1.

3.1.2 Classification of Vehicles

The long history of automobile technology has led to a wide spectrum of vehicle types (see Table 3.1) [7].

Depending on use and construction, the EU legislation classifies street vehicles with their own engines according to Directive 71/320/EEC in two classes (see Table 3.2) [8].

| m of vehicles | | |---------------|--| | | | | Syste | | | Table 3.1 | | | | |

Motor vehicles
Cars Buses mmercial
Co		 Trailer Vehicle Motor vehicle with trailer
vehicles mbination
co
Motorcycle Sedan Minibus Light Heavy freight
trailer		 Car train Car with trailer
Motor scooter Convertible Regular bus m
Mediu		 Bus trailer Motor coach train Bus with trailer
Bicycle with auxiliary
engine		 Station wagon Over-country
bus		 Heavy Station wagon Tractor train mmercial vehicle with
trailer
Co
Special car Trolley bus Tractor Special trailer Tractor with trailer
Multipurpose
car		 Articulated bus
Class Description Groups Number of
people		 Gross vehicle weight rating
(GVWR)
M Transport of
people
(min. 4		 M1 Up to max. 9 M1 with
GVWR B 2,500 kg
M1 with
2,500 kg B GVWR \3,000 kg
wheels) M2
M 3		 Over 9 GVWR B 5,000 kg
5,000 kg \GVWR
N Transport of
goods
(min. 4
wheels)		 N1 Cl. 1
N1 Cl. 2
N1 Cl. 3
N2
N3		 N.A. GVWR B 1,305 kg
1,305 kg\GVWR B 1,760 kg
1,760 kg\GVWR B 3,500 kg
3,500 kg\GVWR B 12,000 kg
12,000 kg\GVWR

Table 3.2 Classification of motor vehicles in the European Union

Table 3.3 Classification scheme of the EPA

Vehicle GVWR
lb (kg) lb (kg)
LDTa B8,500 (B3,855) LLDTc
Light HDDEd		 B6,000
8,501–19,500		 (B2,721)
(3,855–8,844)
HDTb [8,500 ([3,855) Medium HDDE
Heavy HDDE		 19,501–33,000
[33,000		 (8,844–14,966)
(14,966)

According to the European classification, cars and light duty vehicles (LDVs) with GVWR under 3.5 t belong to the classes M and N1, mid-size vehicles with GVWR from 3.5 to 12 t belong to the class N2, and HDVs with GVWR over 12 t belong to the class N3.

The EPA classification has four main groups (see Table 3.3) [9].

In Japan, light cars ''Keijidosha'' are less than 3.4 m (11.2 ft) long, 1.48 m (4.9 ft) wide, and 2.0 m (6.6 ft) high. The engine has a cubic capacity of less than 660 cm3 , i.e., 40 cu in. Compact size vehicles commonly called ''5 number'' vehicles are up to 4.7 m (15.4 ft) long, 1.7 m (5.6 ft) wide, and 2.0 m (6.6 ft) high. The engine's cubic capacity is up to 2,000 cm3 , i.e., 122 cu in [10].

3.1.2.1 Passenger Cars

There are considerable differences in construction and operation among types of cars. Average low powered cars provide an engine cubic capacity from of 1.2–1.6 l, i.e., 75–100 cu in DI technology and operate with three or four cylinders. High-powered

a LDT light duty truck b HDT heavy-duty truck c LLDT light light duty truck d HDDE heavy-duty diesel engine

Table 3.4 Distance per hour, performance of engine, energy consu mption per hour, and acceleration depending on car class
Class of car Distance Performance Energy consu mptionc Accelerationb
mi)
km
(		 (HP)
W
k		 Wh
k		 MJ (BTU) (s)
Low power 140–170 30–40 12–20 43–72 40,973–68,243 15
(87–106) (40–54)
Middle class 170–200 147–221 20–30 72–108 68,243–102,364 12
(106–124) (197–297)
Upper and SUVa over 200 240–250 30–32 108–115 102,364–136,485 9
(over 124) (322–336)

Sport utility vehicle

From 0 to 100 km h-1 , i.e., from 0 to 62 mph Converted to 100 km

Class of car CO2
emissions
g km-1		 Diesel fuel
consumption
l (100 km)-1		 mpg US mpg UK
Low power 100–130 3.46–4.50 68.03–52.31 81.64–62.78
Middle class 130–180 4.50–6.23 52.31–37.78 62.78–45.34
Upper and SUVa 180–270 6.23–9.35 37.78–25.15 45.34–30.21
Land rovers 270–390 9.35–13.59 25.15–17.31 30.21–20.79

Table 3.5 CO2 emissions and fuel consumption of average European cars

upper class cars have an engine cubic capacity of 5.0–5.5 l, i.e., 312.5–343.7 cu in, and contain a 10 or 12 cylinder engine.

Fuel consumption parameters depend on the main construction parameters (see Table 3.4) [11].

Table 3.5 shows the average CO2 emissions and fuel consumption measured according to the New European Driving Cycle [12].

Best results (3.4 l (100 km)-1 , i.e., 69.2 mpg (US) and 83.08 mpg (UK)) can be achieved with internal combustion engines in low-powered cars, using a turbocharged, three cylinder 30 kW (41 HP) self ignition engine [13].

A middle class car powered by natural gas uses 4.0–5.0 kg (8.8–11.0 lb) of natural gas per 100 km (62.15 mi) and emits 100–140 g of CO2 per km (5.68– 7.95 oz mi-1 ). Natural gas-powered cars emit 20% less CO2 than cars with fossil fuel combustion in the engine [14].

3.1.2.2 Light Duty Vehicles

Light duty vehicles are on average 7–8 m (22.95–26.23 ft) long, 2.5–3.0 m (8.20– 9.84 ft) high, 2.0–2.5 m (6.56–8.20 ft) wide, have a GVWR of 5.0–5.5 t (11,023– 12,128 lb) and can carry 13–15 m3 (9.95–11.47 yd3 , i.e., 458.9–529.5 ft3 ) of freight [15].

The fuel combustion and exhaust gas emissions of LDVs are between cars and HDVs.

The cold start at temperature of 20C (68F) should not last longer than 15 s. Electrically heated radiators or burners can lead to lower fuel consumption and emission especially in very cold weather [16].

In Europe, modern LDVs have to meet the requirements of the exhaust gas norm Euro 5 and they will have to meet the Euro 6 norm in 2014. These directives require special exhaust gas after treatment systems. The passive filter system consists of a filter and a catalyst module without electronics and an engine control system. It removes about 70% of particles. Active filter systems are always connected to the Engine Control Unit to be regenerated as required by the cleaning process. The filtering rate in active filter is better than in passive filters; however,

a SUV sport utility vehicle

3.1 Road Vehicles 39

Fig. 3.2 Elements of active and passive safety

the costs of the highly complex system are much higher than in the more simple passive fitter systems.

Regular maintenance of LDVs is necessary after 90,000–100,000 km (55,890– 62,100 mi). Guarantee intervals for engines in Europe are limited to 200,000 km (124,200 mi) or 2 years, depending on which limit is reached first [17].

3.1.2.3 Heavy-Duty Vehicles

In Europe, Heavy Duty Vehicles (HDVs) have a GVWR over 12,000 kg. They usually use a six cylinder self-ignition in-line engine with four valves per cylinder, a Common-Rail direct injection system, a turbocharger and an Exhaust Gas Recirculation also often known as an Exhaust Gas Refeeding system. The cubic capacity is on average between 12,000

and 13,000 cm3 (0.42–0.46 ft3 ) and the maximum performance is 330–360 kW (448–489 HP or 313–342 BTUs-1 ) in the range of 1,000–1,300 rpm [18].

The wheel distance amounts to 4.5–4.8 m (14.75–15.79 ft), the unloaded weight to 12,000–12,500 kg (26,460–27,563 lb) and the GVWR to 25,000– 28,000 kg (55,125–61,740 lb). The tank volume contains about 600 l (21.20 ft3 ). The fuel consumption is between 30.0 l (100 km)-1 (7.84 mpg (US), i.e., 9.41 mpg (UK)) and 32.0 l (100 km)-1 (7.35 mpg (US), i.e., 8.83 mpg (UK)) [19].

The power transmission is carried out with an automated 12 gear but newest models contain a manual transmission up to 16 gears with a transmission factor of 4.0–5.0. The cubicle is usually equipped with four seats. Braking is carried out using disc brakes [20].

Fig. 3.3 Main structural elements of airplanes

3.1.3 Influence of Light Weight Construction on Fuel Consumption

Tendencies in light weight construction are decreasing fuel consumption and exhaust gas emissions. Although new development has resulted in alternative materials, conventional steel sheets are still primarily used for the construction of the vehicle's body. Alternative materials cannot replace steel yet because of its mechanical qualities of resistance, strength and plasticity as well as its cost. The practical way to reduce weight is to use smaller thicknesses and higher quality steel. The steel sheets that are currently used, are between 0.6 and 1.0 mm (0.024– 0.039 in). High Strength Low Alloy (HSLA) steel is used for construction, which allows the use of thinner metal sheets also in stressed structural parts [21].

Since 1994, aluminum bodies have been used for serial production of higher priced vehicles by stamping profiles out of aluminum. Today, aluminum can be used to reduce the weight of specific body parts like the hood, and the trunk lids, etc. The development is requiring more suitable aluminum-based alloys, new production methods, and special repair facilities. Some physical properties such as resistance, deformation, and distortion qualities of high strength aluminum alloys are equal or similar to the qualities of steel sheets, so they can be more and more optimally used in a lot of parts of a vehicle's construction [22].

Light plastic materials are increasingly being used in vehicle construction. New ''self-strengthening'' plastics could allow the cars to be constructed using recyclable polypropylene plastic [23].

However, higher safety rules require a well-balanced compromise between minimizing construction weight and maintaining the commercial and operational competitiveness of passenger cars and LDVs. Safety is the sum of smooth driving, tight steering, optimal suspension, and brakes resulting in the high quality performance of the vehicle [24].

3.1 Road Vehicles 41

Fig. 3.4 Review of flying apparatus

In safety technology, the first important task is to prevent accidents; the second is to lower the number of injuries from accidents by using active and passive safety technology; see Fig. 3.2.

Designed for passive safety, modern cars use not only lightweight materials, but also new vehicle geometries and components that can act as energy-absorbing crumple zones. Modern light cars achieve the performance of a conventionally designed heavy vehicle. More over, they usually provide a larger and highly safed space for crashes [25].

3.2 Airplanes

Aviation began to develop about 120 years ago with the first winged airplanes which were powered by four stroke engines. Fuel consumption at this pioneering time did not play a decisive role. Development was fast and more than 2,100 airports were already in existence in the USA in 1932. In the decades after the Second World War, light weight materials, jet engines, and computer technology began to have more and more of an effect on the development of aircraft construction [26].

Currently, general aviation is defined as all aviation other than scheduled commercial and military aviation.

In 2010, there were 320,000 active general aviation aircrafts and helicopters worldwide, including 17,770 passengers and 89,129 military airplanes, and 26,500 civil and 29,700 military helicopters.

In addition to this number, there were also 4,000 private jets, according to the statistics of General Aviation Manufacturers Association (GAMA) [27].

The number of airplanes in the world has increased rapidly over the last decades. Worldwide general aviation billings rose by 1.2% to US \$19.7 billion due to large-cabin, long-range aircraft.

About 6,000 Instrument Flight Rules flights are in the air at peak travel times.

Number of jet engines

Table 3.6 m of airplanes heavier than air
Syste
Use of plane Weight class Takeoff and Operational range Wing Wing Propulsion
landing mbly
asse		 mbly
asse		 type of jet
facilities order mber
nu		 engines
Traffic According to the guideline of the Land Short (\1,000 km, i.e., High One Four stroke One
international and national organizations mi),
540 n		 engine with
of the civil aviation propeller
Journey Water m 1,000 to
Middle (fro		 Shoulder One and a Jet engine Two
m 540
3,000 km, i.e., fro		 half
mi)
to 1,620 n
Business Amphibious Long ([3,000 km, i.e., Middle Double, Three
airplane mi)
1,620 n		 three
Armed forces Low Multi Four
Sport and Multi
acrobatic
formation

Table 3.7 Main parameters of basic types of airplanes

Type of airplane Seats Speed Cruising altitude m range
mu
Maxi		 Body length Wing span Engines Total thrust
km h-1 m km m m kN
mi h-1)d
(n		 (ft) mi)
(n		 (ft) (ft) (lbf)
mall turbopropa
S		 72 667 7,620 2,522 32.84 28.42 W150A
P		 165
(360) (24,984) (1,362) (107.7) (93.18) (37,095)
Single aisleb 160 750–850 12,000 4,500 39.5 34.3 M56-7B26
CP		 336
(405–459) (39,344) (2,430) (129.5) (112.5) (75,539)
Twin aislec Over 500 995 13,115 15,200 73.0 79.8 Trent 900 313
(537) (43,000) (8,207) (239.5) (261.6) (70,368)
Military transportere 100–150f 620–630 3,000 25–30 35–40 W/engine
3,500 k
(335–340g) (1,619)h (82.0–98.4 ft) (114.8–131.1)i (4,698 HP/engine)
Military tankerj 2,000
(1,080)k

Bombardier Q-400 [37]

Boeing B737-800 [37]

A380-800 [35] Speed in nautical miles per hour or abbreviated as KTS knots per hour

C-130J: Above 15 m (49.3 ft) obstacle the takeoff distance is 1,400–1,500 m (4,590–4,918 ft), and the landing distance is 700–800 m (2,295–2,623 ft) [38]

Soldiers or paratroopers, 3–10 system operators, 1–2 loading foreman [38]

The maximum speed is 670–680 km h-1 , i.e., 362–368 nmi h-1 [38] Special transporters reach the maximum distance of 6,500 km (3,510 nmi) [38]

The wing area is 150–160 m2 , i.e., 1,613–1,720 ft2 [38]

j A330-200: Mass of transported fuel to other airlines is 65 t (143,172 lb) [39]

Maximum cruising time is 2 h [39]

Fig. 3.5 Fuel consumption of modern airline fleets

Fig. 3.6 Material structures of a modern airplane

3.2.1 Main Construction Elements

The main groups of structural elements of an airplane are presented in Fig. 3.3 [28].

3.2.2 Classification of Airplanes

Airplane systems have become very complex (see Fig. 3.4) [29]. However, this book deals only with rigid wing airplanes (see Table 3.6) [30].

3.2.3 Comparison of Fuel Consumption and Exhaust Gas Emissions from Airplane Types

There are three main types of airplanes:

• Small airplanes;

3.2 Airplanes 45

Fig. 3.7 Advantages and disadvantages of plastics

  • Narrow body airplanes; and
  • Wide body airplanes.

Furthermore, there are several special purposed and individually constructed airplanes in military as well as in civilian aviation [31].

3.2.3.1 Small Airplanes

Small airliners usually offer optimal fuel saving economy. In this type of airplanes the fuselage is very narrow. There are from two to four seats in a row. The cabin provides seals for 10 and 80 passengers. The cruising altitude is 7,000–8,000 m (22,951–26,230 ft), and the range is up to 1,500 km (810 nmi) [32].

Airplanes with modern turboprop engines have the lowest Specific Fuel Consumption (SFC). In the future, contra rotating rotors can further improve SFC. However, there are two main problems for a wide ranged application of small turboprop airplanes:

  • They are flying at low altitudes and useing very congested air spaces; and
  • The noise emission level of turboprop engines is high, especially that of contra rotating propellers.

Improving these features and fulfilling requirements needs further intensive development in the near future.

3.2.3.2 Narrow Body Airplanes

Narrow body or single aisle airplanes usually fly middle distances at altitudes of 12,000 m (39,344 ft). They have a maximum of six seats in the cabin in a row. New narrow body airplanes using turboprop engines with contra rotating

Ships Years
2005 2006 2007 2008 2009
Tankers 368.4 387.7 411.0 439.3 463.3
Bulk goods 319.2 341.7 363.6 386.6 414.4
Container ships 99.2 1,117.7 128.2 144.6 161.9
General cargo 95.3 97.4 100.6 102.8 106.8
Passenger ships 5.9 5.9 6.1 6.2 6.4
Total 888.0 944.4 1009.55 1,079.55 1,152.8

Table 3.8 Development of the international maritime fleet from 2005 to 2009 in 106 DWT

propellers provide very low SFC. However, the field of civil application is currently limited narrow body airplanes do not use long distances. Through new innovations, this situation could be changed in the future [33].

3.2.3.3 Wide Body Airplanes

Wide body airplanes normally have a cabin with a large diameter, provide twin aisles, use turbofan engines, and fly middle or long distances. They are more fuel efficient than narrow body single aisle airplanes with the same or similar turbofan engines but do not reach the particularly low SFC of turboprop engine-driven small airplanes with contra rotating propellers which have an extremely high efficiency [34].

The newest and largest passenger airplanes (A380 and B787) use a very high portion of glass fiber strengthened composite substances and sandwich construction to reduce the weight [35, 36] Optimal aerodynamics, efficient main and auxiliary engines, and modern electronic technology in Very Large Airplanes (VLAs) save fuel and operating costs by up to 10–15% in comparison to mid-size airplanes. In addition to the basic models, new freight and long-range types with a shorter fuselage are in development.

Table 3.7 shows examples of recent airplane types.

3.3 Influence of Weight Reduction on Fuel Consumption

The consumption of fuel in airplanes depends on many factors, similar to other types of transportation means. International Air Transport Association (IATA) data show an exponential decrease of fuel consumption per passenger kilometer [40]. There has been a 23% reduction on average over the last 30 years; see Fig. 3.5 [41].

The fuel consumption rates of modern wide body airplanes are about 3.0–3.2 l per passenger-kilometer per seat, i.e., 1.469–1.567 gal (US) or 1.223–1.304 gal (UK) per passenger-nautic mile per seat.

Fig. 3.8 Development of the world Total Seaborne Trade (TST)

Fig. 3.9 Main structural elements of a merchant vessel

3.3.1 Optimization of Takeoff Mass

Fuel makes up a high proportion (near 50%) of the takeoff mass of airplanes. The B767-200/200ER, a modern long-range, wide body, twin aisle airplane has the maximum takeoff weight of 179,170 kg (395,070 lb), the empty weight of 86,000 kg (189,630 lb), and the maximum freight load of 30,000 kg (66,150 lb). Tanks contain approximately 73,000 kg (160,965 lb) of fuel which allows for flight time of 15–16 h, i.e., 12,500–13,333 km (6,749–7,199 nmi). Safety regulations require additional fuel of 7,000 kg (15,435 kg) to make it possible to fly an extra time of 1.5 h. This equals to the distance of 1,200–1,300 km (648–702 nmi) or the weight of 70–75 passengers [42].

3.3.2 Use of New Construction Materials

Aluminum has been the first new material used in construction and its application resulted in lower weight and decreased operational and maintenance costs by 50%.

m, and type and construction material of ships
Field of use, propulsion syste
Table 3.9

Field of use, propulsion syste
Table 3.9		 m, and type and construction material of ships
Field of use Propulsion system Type Construction material
Sea navy Paddle wheel Manpower driven rowing boat,
galley		 Aluminum
Open sea navy Sail Sailing ship Concrete
Coastal navy Propeller drive Steam engine ship Iron
maller inland lakes,
rivers and channels)
Inland navigation (s		 Jet drive Diesel engine ship Wood
Fishery (sea, coastal, open sea) Voith-Schneider-drive Gas turbine ship Steel
Pod-drive Nuclear engine ship
Nuclear submarine		 Simple plastics
Z-drive Solar ship Reinforced plastics with glass
and carbon fiber
Fuel cell ship
Historical purpose
Freighter Scow, row boat, barge Fire protection ship Rescue cruiser
Line freighter Special ship Cable layer Icebreaker
Tramp steamer Vehicle transporter Pipe layer Passenger ship
Container ship Folding ship Fishing boat Ferry boat
Tanker LASH carriera Whaling mother ship Battle ship
Chemical tanker Labor shipb Marine technique Aircraft carrier
Gas tanker Hauler Fire service ship Sport boat
Bulk goods freighter Batch ship Cruise ship Recreational craft
Cooling ship Thrust lighter Research ship Coffee boat
Piece goods ship Pusher tow Marine emergency Dinghy
Ro-Ro ship Offshore ship Yacht
FSOc House boat
Historical ship

Lighter aboard ship b Indentured servant c Floating storage and offloading

Table 3.10 Main types of ships

Ship type Technical description
Bulk carriers Bulk carriers are cargo ships used to transport bulk cargo items such as ore
or food staples, e.g., rice, grain, and similar cargo [56]. There are double
or folding bulk heads. For balance, bulk carriers have lower and upper
wing tanks. The bridge is installed near the stern. The ships usually have
five to nine holds, often of different lengths. The transverse bulkheads
are either designed as double bulkheads or as folding bulk heads
Container ships Container ships carry standardized 20 or 40 TEU containers [57]. There are
also different lengths. Today all container ships are propelled by diesel
engines and reach speeds of 24–27 kn, depending on their size and
service. Feeder ships sail with 19 kn or less. Container ships have a lot of
open spaces on the main deck which reduces the torsion rigidity of the
ship's hull
Ro–Ro ships Roll-on and roll-off ships or ''Ro–Ro'' ships are cargo ships designed to
carry wheeled cargo such as automobiles, trailers or railway carriages
[58]. The vehicles enter and leave the ship after arrival at the port of
destination
Refrigerated ships Special refrigerated ships are used for the transport of perishable foods such
as meat, fish, or fruits and vegetables [59]. These ships are developed
from the usual dry cargo freighters but they have a higher speed and
appropriate cooling equipment including extensive insulation
Tankers for liquid
cargo		 Liquid cargo is generally carried in bulk aboard tankers, such as oil,
chemical and LNG tankers [60]. Tankers have a closed main deck, apart
from the relatively small tank hatches, which influence the stability of
the ship to a limited extent. If the ships run aground or are involved in
collisions, large quantities of oil could spill. Therefore, the ship has to be
equipped with a double bottom and a double outer skin. Recent
legislation still provides for the phasing out of a single bottom
construction tankers.
DWT of large oil carriers is usually above 300,000 t (661 9 106 lb)
and
the engine's performance is 25,000–28,000 kW (33,557–37,584 HP).
The ships achieve a speed of 15–16 kn
LNG carriers are on average smaller than oil tankers and reach a DWT
of 10,000–12,000 t (22.1–26.5 9 106 lb)
[61]. The capacity is 50,000–
70,000 m3 ((1.79–2.50)
9 106 ft3
), and the engine performance is
5,000–6,500 kW (6,711–8,725 HP). The refrigerator cools 5,000–
10,000 m3 ((0.179–0.357)
9 106 ft3
) gas per hour on average at the
temperature of -164C charging the liquid gas containers for 8–12 h
Passenger ships Passenger ships range in size from small ferries to large cruise ships [62].
Ferries move passengers and vehicles on short trips. Ocean liners carried
passengers on one-way trips in the past. Cruise ships transport
passengers on round-trip voyages promoting leisure activities on-board
and in the ports. High speed ferries and warships use turbines which
resemble those of airplanes. Most passenger ships use a diesel engine

In 1982, plastics made up only 8% of an airplane. Now, complete airframes are produced entirely from composite materials. Current plastics, made of carbon fiber, glass fiber, or composite substances with nano tubes are on average up to 50% lighter than aluminum [43].

Examples of vessels' operation parameters
Table 3.11

Table 3.11 Examples of vessels' operation parameters
Parameter WT
D		 GT LOA Beam Draught Main engine
Ship type 1,000 t 1,000 t m m m output
(106 lb) (106 lb) (ft) (ft) (ft) W
M
)
(BTUs-1
Bulk carrier 160–180 85–87 280–300 44–48 17–19 55–63
(352–396) (189–192) (921–984) (145–158) (56–63) (52,182–59,772)
General 9–10 6–7 115–125 18–22 8–10 7–10
cargo vessel (20–22) (13–15) (378–411) (59–72) (26–33) (6,641–9,488)
Container ship 50a–157b 50–171 200–397 30–56 14–16 40–80
(110–346) (110–377) (656–1302) (99–184) (46–51) (37,950–75,901)
Oil carrier 300–350c 150–160 300–350 55–60 20–22 25–28
(661–771) (330–352) (984–1148) (181–197) (66–72) (23,697–26,540)
mical tanker
Che		 3–4 – 90–100 13–16 – 2–4
(7–9) (296–329) (43–53) (1,896–3,792)
Ro-Ro shipd 9–10 9–10 100–130 20–22 – 7–9
(20–22) (20–22) (329–428) (66–73) (6,639–8,539)
Ferry boate – – 60–65 – – 26
(197–213) (24,669)
Passenger ships 1.0f–19.2g 15–151 30–345 10–41 2.0–9.8 10–86
(2.205–42.336) (33–333) (99–1,132) (33–135) (6.6–32) (9,488–81,594)

Smaller sea-going container ships carry approximately 5,000–6,000 TEU [64] b Emma Maresk, the biggest container ship of the world in 2011, NT 55,396 t, i.e., 122 9 106 lb, container capacity 11,000 TEU, auxiliary engines power 30 MW, i.e., 40,000 HP [65]

Knock Nevis Supertanker 564.65 DWT

Speed 14–15 kn, TEU 500–560, year of construction 1975–1980 [66] e High speed ferry with 208 passengers plus 45 cars along 180 nmi, speed 52 kn (96 km h-1 ) with water jet propulsion [67] f Small passenger sea-going ships with a speed 17–18 kn, i.e., 32–34 km h-1 [68] g Queen Mary 2 [69]

In modern airplanes, the tail segments, the fuselage, the wing and the wing stabilizers, the skin, the spoilers, the leading and the trailing edge flaps, the engine inlet, and the aerodynamic cones are made of composite materials (see Fig. 3.6).

Interior cabin furnishings and passive interior noise treatment, e.g., wall insulation for cabin noise may be reduced in the future if active noise control technology is developed. However, passive noise controls, i.e., insulation blankets are normally not only used for noise reduction, but also for heat insulation. Reducing insulation would require more power for heating and cooling [44].

The newest airliners' major structural elements are completely made from Kevlar and CFC materials. Certification of this technology has been completed [45].

The disadvantages of most plastic materials are their higher rigidity and the lower conductivity. Many plastics are still too ductile to be used as airfoils as they tend to break under constant load; see Fig. 3.7.

Military aviation started to use Carbon Fiber Reinforced Plastic (CFRC) materials approximately 20 years earlier than civil aviation [46]. Since that time, glass fiber strengthened composite materials have been increasingly used not only in civilian airplanes but also in military airplanes and helicopters. Even modern fighters which are subject to enormous loads in flight, use more plastic components. As experience has shown, the loading gate of future military airplanes can be completely manufactured from CFRC.

3.4 Construction of Ships

The age of industrial shipbuilding began in the middle of the nineteenth century with steam ships which continued to be built until the first oil crisis in 1973. The propulsion system contained the coal bunker, the steam engine, and later the oilfired boilers and steam turbines. In recent decades, marine engine technology has been continuously changing [47]. In the last 10 years, maritime shipping has rapidly developed, compared to the previous centuries or millennia.

Today, there are more than 43,349 civilian ships over 1,000 GRT. Panama (6,124), Liberia (2,162), and China (1,822) lead the rankings. Besides cargo and passenger ships approximately 4 million fishing vessels are also consuming fuel and emitting exhaust gas pollutants and GHG gases [48].

In 2009, the international merchant fleet consisted of 40% tankers, 36% bulk carriers, 14% container ships, and 9% other ships; see Table 3.8 [49].

The quantity of freight transported by ships is intensively increasing. In 2010, the shipping industry transported over 10,000 million tons of cargo, equivalent to a total volume of world trade by sea of over 42,000 billion ton-miles; see Fig. 3.8 [50].

Total cargo has increased by 8% over the previous years. Today, shipping contributes between 1 and 5% to the international GDP [51].

The average age of the international fleet, including ferry boats and special ships is 18.6 years. The oldest types of ships are reefers and passenger ships with an average age of more than 25 years. Container ships and tankers are the newest types of ships on the sea [52].

3.4.1 Main Construction Elements

The basic construction of a merchant vessel is shown in Fig. 3.9.

The hull is subject to various hydrostatic and hydrodynamic constraints [53]. Therefore, it must be able to support the entire weight of the ship and maintain stability even with unevenly distributed weight. Furthermore, it must withstand the shock of waves and all weather conditions. Hulls are made of steel, but aluminum can be used on faster craft. Glass fiber can be used for the smallest vessels or for sport boats [54].

3.4.2 Classification of Ships

Ship technology is an important part of modern commercial and military transportation. According to the old history of navigation the field of use, the propulsions system, the type and the construction materials of ships are variable and multilayered (see Table 3.9) [55].

3.4.3 Type of Ships

There is a very variable selection system of seagoing and inland ships of vessels and passenger ships. One aspect of distingation in the construction. A further criterion is the application in civil and in military service. In this context submarines mean a specific class.

The main characteristic parameters of ships are contained in Table 3.10.

3.4.4 Comparison of Fuel Consumption of Ships

Merchant vessels are becoming ever larger to adjust to the load requirements and to decreased fuel consumption. Table 3.11 shows the main operation parameters of several types of vessels [63].

The Queen Mary 2, one of the largest ships of the world, has an engine which performs at 4 9 21.5 MW, i.e., 86 MW (two fixed and two azimuthing), i.e., 115,436 HP. The installed board power reaches 126.7 MW (170,067 HP) which is higher than the engine power. At an average speed of 30 kn, i.e., 56 km h-1 , the fuel consumption is 252 t d-1 , i.e., 555,066 lb d-1 at an average speed of 30 kn, i.e., 56 km h-1 . It equals to 40–45 ft per 1 gal (UK), i.e., 12.2–13.73 m per 4.546 l of navy oil or 6.6–6.0 9 10-3 nmi gal-1 (UK) or 7.9–7.2 9 10-3 nmi gal-1 (US).

Container ships intensively vary in size, construction, and power. The largest containers ships have an 8–14 cylinder engine. Container transport must be fast, because goods in the containers have to be delivered to the customers as soon as possible. The SFC is between 163 and 170 g kWh-1 (1.68 9 10-3 –1.75 9 10-3 oz BTU-1 ) in a speed range from 25.2 to 27.5 kn maximum, i.e., from 46.7 to 51 km h-1 [70].

The fuel consumption of container ships is approximately half of that of passenger ships in the same category. The largest ships such as tankers with no perishable goods have the lowest level of fuel consumption. They can optimize speed and operation. Comparisons consider a fuel oil viscosity of 730 cSt at a temperature of 50C (122F), according to Fuel Standard ISO 8217.

Modern merchant vessels achieve 120 g kWh-1 , i.e., 1.263 9 10-3 oz BTU-1 which is the lowest level in the transportation sector with internal combustion engines. The interval is wide ranged. In shipping, the highest SFC is provided by fast ferry and specific navy boats with hydrofoil, jetfoil, hovercraft, fast monohull, and catamaran technology which have a SFC above 220–250 g kWh-1 , i.e., 2.317 9 10-3 –2.632 9 10-3 oz BTU-1 . The consumption rates are related to the rpm [71].

3.4.5 Influence of New Construction Principles on the Fuel Consumption

Transportation by water is significantly less costly than transportation by road or air. In civil shipping, construction, size, and load decide fuel consumption. Small cargo ships consume fuel IFO 380 at a rate of 10–20 t d-1 (22,050– 44,100 lb d-1 ), light freighters 20–25 t d-1 (44,100–55,125 lb d-1 ), and large cargo ships 50–55 t d-1 (110,250–121,275 lb d-1 ).

War ships consume much more fuel than civil ships because of the high weight, high speed, and high energy demand of engine system and special equipment. A destroyer of 14,000–15,000 DWT displacement consumes fuel 1,000–1,200 t d-1 ((2,205–2,646) 9 103 lb d-1 ).

Enlargement of ships has clear limits. So increasing ship's size and traffic intensity require new construction principles for higher safety on sea.

3.4.5.1 Double Bottom

Double bottom technology has been introduced in container ships first, later in bulk carriers, tankers, and then in other ships. For this type of construction is the reduction of corrosion, material fatigue, crack formation, overloads, and damage especially important [72]. However, double bottom technology contributes to higher manufacturing and operating costs and higher SFC.

3.4.5.2 Fast Mono Hull Concept

The fastest ships are catamarans because of the very low hydrodynamic resistance. Fast mono hull designs cannot achieve the same maximum speed, but they are more economical and can be used for all kinds of fast ships, such as fast passenger ships, ferries, container ships, refrigeration, and Ro–Ro ships.

The optimal streamlined form and the specific smooth surface of the hull reduce the resistance of waves below the waterline. Above the waterline the construction increases the crossways stability and the usable space. Ever larger hulls are being constructed with reduced specific weight through the use of high-strength shipbuilding steel instead of normal quality steel. Furthermore, in fast construction, the stern is optimized for the propeller to work at high speed.

In the shipping fast catamaran and mono hull constructions consume the highest specific rate of fuel and emit the highest specific volume of exhaust gas pollutants [73].

3.4.5.3 Common Structural Rules for Designing and Monitoring Construction

Ships for the North Atlantic are expected to be in service for 25 years. Therefore, hull scantlings and steel distribution must be constructed in accordance with the Common Structural Rules (CSR) [74]. CSR does not require a radical change from the existing rules, but it raises specific issues concerning structural strength, corrosion, watertight integrity, and fatigue.

The CSR multi-purpose software supports the design and analysis of hull structures and the cross-section of vessels. The main aim is to minimize the additional amount of steel required. Computer software determines the scantlings of all structural components automatically based on requirements for the vessel's size, shape, weight, class, cargo load, and fuel consumption.

3.5 Summary and Recommendations: Construction Technology

Construction has a significant impact on fuel consumption in all types of transportation. Light weight construction is gaining a leading role in development. Computer supported construction methods decrease costs and increase quality. Additionally, technological development often requires financial, organizational, and social measures, too.

3.5.1 Road Vehicles

In cars, despite the possibilities for lighter construction that developments in material technology have provided, new vehicles are becoming heavier because of the increased requirements regarding safety and comfort with power steering, airbags, electronic stability programs, strengthened chassis, air conditioning, etc. The trend also affects heavier commercial vehicles such as buses and trucks.

Vehicles with lighter weight have less rolling and acceleration resistance and therefore decreased fuel consumption. Besides transmission elements, especially the wheel structure and tires wear faster at higher speeds and with greater loads.

In city traffic, fuel consumption and emissions are approximately 20–30% higher, depending on traffic, than on highways or country roads.

In addition to technology, there are other important parameters, which significantly impact fuel and emission savings, e.g., safety, fuel type, car occupancy and traffic organization, etc. Most cars with four or five seats are rarely used at full capacity. This parameter can be improved by education, and organization measures. Congestion and urban sprawl also lead to inefficiencies in fuel consumption and emission savings. For improving recent situation, traffic organization can be improved through the use of computer-aided traffic steering and navigation measures.

3.5.2 Airplanes

The main structural elements of an airplane are the fuselage, the wings, the tail unit, and the landing gear. Planned range, payload, speed, and altitude are decisive for the construction.

The trend has continued toward larger and more comfortable airplanes in the last decades. Their dimensions and weights are increasing despite the use of lighter CFC materials. In the same time interval, parallel to it, new constructions lead to lower SFC and decreased specific operational costs.

Airplanes must be designed to be able to operate as economically as possible and with maximum versatility. The structure, the range, the payload, the fuel consumption, and the exhaust gas emissions of an airplane are always closely related. Any increase in flight distance and payload raises the amount of fuel. For safety reasons, the payload of an aircraft must be reduced, in favor of the fuel amount required when the sum of required fuel and intended payload would be in conflict with structural and operational limits of the aircraft.

There is a high demand for low weight airplanes predicted for the whole century. However, a lot of existing options for reducing the size and weight are limited by practical reasons for production, safety, and finance.

3.5.3 Ships

Similar to other means of transportation, development in construction strictly defines the durability, the inspection, the maintenance, the fuel consumption, and the exhaust gas emissions of ships. Hull materials and size play a large part in determining the construction technology. The hull of a glass fiber sailboat is constructed from a mold. The steel hull of a cargo ship is produced from large sections welded together. The weight is reduced through the intensive use of highstrength shipbuilding steel instead of normal quality steel. Light weight materials are used in the construction of the deck and the equipment.

Extremely low hydrodynamic resistance is provided in fast ships like fast passenger ships, ferries, container ships, refrigeration, and Ro–Ro ships. Besides catamaran technology, the fast mono hull construction provides the highest speed. However, not only the higher fuel consumption and higher exhaust gas emission rates, but also the higher operational costs make the high speed technology very expensive.

Ships are the most fuel efficient means of transportation. Merchant vessels containing large, two stroke marine diesel engines have a SFC of about 120 g kWh-1 , i.e., 1.24 10-3 oz BTU-1 . Passenger ships, depending on the equipment, have a SFC of 180–200 g kWh-1 , i.e., 1.86 9 10-3 –2.07 9 10-3 oz BTU-1 and fast ferry boats have a SFC of 220–250 g kWh-1 , i.e., 2.37 9 10-3 –2.63 9 10-3 oz BTU-1 .

References

References 57

Chapter 4 Fuel System and Fuel Measurement

The fuel economy of SFC of the engine is usually measured on the test bench under nominal conditions and represented in a consumption identification diagram. The real fuel consumption in travelling, flying and shipping normally differs from the consumption on the test bench. Road vehicles', airplanes', and ships' real fuel consumption depends on the performance, load, speed, and operation conditions at first.

The Type Approval (TA) of the road vehicle's, ship's, or airplane's engine has been developed for examinations at the test bench with defined test cycles. The analyzers are usually large devices certified by national authorities.

The direct method is the measurement of fuel consumption. The indirect method is the analysis of carbon emissions and then mathematically calculating the fuel consumption on the basis of the CO2 balance [1].

Currently, fuel consumption is monitored by small sensors with a quick response time. Their basic principles are conductivity, capacitivity, ultrasound technology, and radiometry. Figure 4.1 shows the different variants of fluid flow measurement [2].

Depleting the tanks is to be strictly avoided in all types of vehicles, aircrafts, and ships. The amount of fuel in a tank is usually measured by static pressure or capacitive sensors at the bottom of the tank and by a floating switch at the surface of the fuel. Few methods continuously estimate the fuel flow in the fuel pipe between the tank and the engine. Combinations of static and dynamic control methods are useful for safety reasons.

Fuel management systems record fuel consumption, fuel transfer, and refilling of tanks. Fuel management considers the daily consumption of the entire fleet, down to individual fuel tanks and maintains a complete history of all events, providing reports for billing purposes and integrating timely fuel inventory.

Fleet wide fuel purchase, fuel consumption, and, in the future, emissions, i.e., the complete financial system can be continuously controlled by using the Internet [3].

Fig. 4.1 Measurement technologies in fluid flow

4.1 Fuel System in Vehicles

The fuel tank is the central element of the supply system. It is made of surface treated steel or plastics according to the space requirements in vehicles, airplanes, and ships [4].

In road vehicles, the fuel system consists of a filter, a small reserve tank as a fuel reservoir for use when the vehicle is not level on a curve, an electric diving pump, a fuel level, a pressure, and in special cases a flow sensor as well as electrical and hydraulic connections; see Fig. 4.2.

The fuel is pumped from the fuel tank into a pressure regulator, which keeps the pressure of the fuel constant, and forced through a fuel filter, a mass control valve, which controls the mass flow independent from the fuel level in the tank and at the end of the supply chain to the CR system with a regulator and control sensor.

When electronic fuel injection was first introduced, the electric fuel pump was always outside the tank. In new vehicles it is more common to have the fuel pump installed within the tank. Fuel pumps must supply the engine with sufficient fuel under all operating conditions with the pressure necessary for injection. The essential requirements of pumps are:

high pressure pump with mass control

Fig. 4.2 Tank system of a car with a self ignition engine

  • To provide a flow capacity between 60 l h-1 (15.85 gal h-1 (US), 13.20 gal h-1 (UK)), and 200 l h-1 (52.84 gal h-1 (US), 44.03 gal h-1 (UK)) at nominal voltage; and
  • To regulate the pressure of the fuel system between 300 kPa (6,277 lbf ft-2 ) and 450 kPa (9,416 lbf ft-2 ) [5].

In addition, electric fuel pumps are increasingly used for modern direct injection systems, both for spark and self ignition engines at 700 kPa (14,647 lbf ft-2 ). This high pressure and the very wide viscosity range of diesel fuel mean new challenges for the hydraulic and the electric systems of fuel pumps.

Several new production designs of fuel tanks are being developed to lower emissions from the tank. Brush-less pumps and new fuel level sensors are under development [6].

4.1.1 Fuel Measurement

Current requirements for analyzing fuel consumption present a high level of technology. Driving cycles with artificial conditions create uniform and comparable conditions for the determination of fuel consumption.

The measurement of fuel consumption in the EU is based on the NEDC according to the requirements of the guideline 80/1268/EEC, Appendix 1, amended by 93/116/EC and ECE-R101 [7, 8]. Fuel consumption is determined by a cycle simulating urban driving as described in 70/220/EEC, Annex II in:

  • Constant speed test at 90 km h-1 ; and
  • Constant speed test at 120 km h-1 [9].

The results of the test are expressed in l (100 km)-1 . The fuel must be supplied to the engine through a device capable of measuring the quantity consumed to within ±2%. This device should not interfere with normal supply. There must be a valve to permit rapid changeover from the general fuel supply system to the measurement system.

4.1.1.1 Car and Light Duty Vehicle Technology

93/116/EC applies to the carbon dioxide emission and the fuel consumption of all motor vehicles of the category M1. The weight of fuel consumed is calculated according to the carbon balance method using the measured emissions of CO2 and other carbon-related emissions (CO and HC):

$$M_{gasoline} = f(CO_2, CO, HC) \tag{4.1}$$

The CO2 emissions are measured during the test cycle simulating both urban and highway driving patterns as described in 91/441/EEC (1), Appendix 1 of Annex III. Test results are averaged and expressed in Europe in g km-1 or g mi-1 [10].

Similar to the EU method, in the USA the measured fuel is based on the regulation 40 CFR Part 600-113 [11]. Fuel consumption is determined on test benches according to the carbon balance method from the CO2, CO, and HC emissions analyzed in miles gal-1 (US) in US EPA II and in Highway Fuel Economy Cycle (HWFET) [12, 13]. In Europe, the fuel consumption is expressed in l km-1 or l (100 km)-1 , in the USA in gal mi-1 or in the most cases, in mpg.

Japan uses synthetic cycles, such as the 11 Mode cold and 10 ? 15 Mode hot cycle, respectively, New Driving Cycle JC 08, which is similar to the NEDC; however, they apply different speeds and gears [14].

The relation between the fuel consumption and the speed of an average midsized car in the NEDC is presented in Fig. 4.3 [15].

According to the statistics, the average fuel consumption of a European mid-class car is 6.2 l (100 km)-1 , i.e., 47.6 mpg (US) and 45.5 mpg (UK). The cold start phase in the first 120–180 s demands an extraordinary large amount of fuel, above 30 l (100 km)-1 i.e., 105 mpg (US) and 126 mpg (UK). The urban fuel consumption in the second phase is 8.2 l (100 km)-1 , i.e., 28.7 mpg (US) and 34.4 mpg (UK) and the highway fuel consumption in the last phase is 5.1 l (100 km)-1 , i.e., 46.1 mpg (US) and 55.3 mpg (UK).

Fig. 4.3 Fuel consumption of an average European car relative to time of NEDC

4.1.1.2 Heavy-Duty Vehicle Technology

Since trucks and buses are too heavy and too large, not the entire vehicle's but the engine's emissions are controlled at an engine test bench with computer-supported driving cycle programs [16].

In Europe, the emissions of heavy-duty vehicles are examined using Directive 70/220/EEC including amendments and corrections. The European Stationary Cycle ESC is a steady-state procedure with a 13-point examination. The European Load Response Cycle ELR has the purpose of opacity determination. In the European Transient Cycle ETC, different driving conditions are represented by three parts, including urban (maximum speed is 50 km h-1 (31.05 mi h-1 ), with frequent starts, stops and idlings), rural (step acceleration segment, average speed is 72 km h-1 ) (44.7 mi h-1 ), and motorway driving (average speed is 88 km h-1 (54.65 mi h-1 ). The duration of the entire cycle is 1,800 s. Each part lasts for 600 s [17].

However, with specific and large test dynamometers, which sometimes have artificial cooling, pressurization, and air humidification, heavy duty trucks and buses can be dynamically controlled for research and development experiments; see Fig. 4.4 [18].

In the USA, the EPA Urban Dynamometer Driving Schedule (UDDS or Cycle D) has been developed for chassis dynamometer testing of heavy-duty vehicles. The

Fig. 4.4 Test bench for heavy duty vehicles

HD-UDDS cycle should not be confused with the FTP-72/LA-4 cycle for light-duty vehicles, which is also termed UDDS [19].

In Japan, 6-Mode Cycle, 13-Mode Cycle, and JE05, also called as ED12, introduced in 2005, based on Tokyo driving conditions, are applicable to diesel and gasoline HDVs over 3,500 kg (7,709.25 lb). The duration is 1,800 s, the average speed is 26.94 km h-1 (16.73 mi h-1 ) and the maximum speed is 88 km h-1 (54.65 mi h-1 [20].

The accelerating and braking properties of the individual driving cycles are different, and therefore fuel consumption and exhaust gas emissions are not directly comparable with each other. Although driving cycles are developed on the basis of country- or city-specific driving conditions, traveling has become more and more similar on the world. Unified driving cycles would simplify testing procedures worldwide.

There are two harmonized cycles, the World Harmonized Stationary Cycle and the World Harmonized Transient Cycle for heavy-duty engines. They can be used for emission certification and TA worldwide [21, 22].

The fuel consumption of trucks and buses is traditionally tested in the journey with a standard engine in a standard vehicle, in standard traffic and in standard environment conditions. The weather must be dry and calm at a certain temperature and a certain air pressure. The examining speed has to correspond to 75% of the vehicle's maximum speed. To compensate for uncertainties, the fuel that was consumed is increased by 10% over the measured distance [23].

Fig. 4.5 Fuel flow during a flight over a distance of 1,000 km

4.2 Fuel System in Airplanes

There is a direct relationship between the volume of the fuel tank, the structure of the supply system, and the flow of the fuel to the engine. The fuel supply system of a jet engine has to regulate opening and closing valves, adjust compressor blades, thrust exhaust nozzles, and operation of the afterburner. It must avoid thermal and mechanical overload, prevent unstable compression, and burning when accelerating [24].

The fuel system of airplanes operates under variable air pressures and temperatures depending on flight altitude, which indirectly influences the combustion chamber temperature, and the compressor pressure.

The fuel consumption of airplane engines depends on the flight phase, i.e., on the load of the engines; see Fig. 4.5.

4.2.1 Fuel Storage and Supply

Aircraft typically uses three types of fuel tanks:

  • Integral tanks which are contained in ''wet wings'' and are applied in larger aircraft;
  • Rigid removable tanks in metal constructions for smaller aircraft; and
  • Bladed tanks for high-performance light aircraft [25].

Multiple engines demand a multiple tank system, consisting of main and auxiliary tanks. Selector valves, jettisoning, and defuel valves regulate the fuel flow; see Fig. 4.6.

The fuel is moved from the tank assembly to the jet engine with a low pressure pump at 8.6 9 105 Pa, i.e., 125 psi, using geared wheel, wing cell, or piston pumps. The fuel in the aircraft fuel tanks cools down at cruising altitudes with an approximate Outside Air Temperature of -40C (-40F) [26].

Fig. 4.6 Fuel system of an airplane

Gear wheel or piston pumps are used for the high pressure circulation system. The fuel regulator unit provides the flow that corresponds to the load. The fuel nozzles distribute the fuel into the combustion chamber. Their number varies according to the construction of the combustion chamber and the size of the jet engine [27].

The fuel is preheated downstream to the low pressure pump to prevent water contained in the fuel from crystallizing into ice which could clog the filters and the regulation valves. The main fuel filter stops particles bigger than 0.03 mm or 1.18 9 10-3 inches [28].

Certain nozzles are used for the starting process and for the higher load ranges. Double channel burners have a primary and a secondary fuel nozzle. The primary nozzle delivers fuel during the start and the idle phases. Above these load ranges, the secondary nozzle takes over the supply of fuel. The diameter of the droplets is 0.05–0.10 mm (1.96 9 10-3 –3.94 9 10-3 in). Primary and secondary nozzles spray droplets into the combustion chamber with an intensive whirl [29].

4.2.2 Fuel Regulation

The regulator of a gas turbine has to provide the proper amount of fuel required under any operating conditions and has to prevent thermal or mechanical overload.

Operations had to be simplified when flight engineers were excluded from the cockpit, because there were more input signals to be controlled by two pilots. This required computers to take over the monitoring function. Fuel management became more complicated due to the permanent increase of requirements regarding jet engines as a whole. The earlier hydro-mechanical regulators have been replaced with a new electronic regulator, the Full Authority Digital Engine Control (FADEC) [30].

The main elements of the FADEC system are the micro electronic system, the sensors, and the actuators, and several elements for signal processing, such as the analog–digital transducers, the multiplexers, and the micro processors. In the airplane redundancy systems two permanently active channels generate signals, including sensors for monitoring the power supply. Modern electronic and micro computer systems enhance the reliability of the FADEC system compared with hydro-mechanical systems.

4.2.3 Fuel Planning

Safety is the most important task in aviation. There must be enough fuel on-board at departure to cover the planned distance, the ground operation needs, and the amount has to meet the regulations for mandatory reserves including engine failure and reaching an alternate airport if necessary after takeoff, climbing, cruising, descent, and landing.

The basic standards regarding fuel are contained in ICAO Annex 6 to the Chicago Convention, establishing the acceptable minimum level of safety for international civil flight operations and are reflected in the national codes. The national codes, such as the Federal Aviation Regulation for US Federal Aviation Administration and the European Operation Performance Standard (EU-OPS) for the European Community, may differ from each other, but must not be less stringent than the corresponding ICAO standard [31]. EU-OPS is very common to JAA-OPS [32].

Conventionally, the planned route must be in close vicinity of airports so that in case of an emergency like an engine failure, the airplane must be able to reach an airport within 60 minutes with one engine inoperative. As a result, instead of traveling straight, the route may become curved, consequently increasing the trip distance and the required fuel.

An airline operator has to decide on the amount of fuel on-board with due regard to IFR for all phases of operation [33].

Figure 4.7 presents the flight segments of a typical trip at an altitude of 1,500 ft (457 m) above departure to landing at the destination [34].

For safety reasons a departing airplane must have a quantity of fuel on-board not less than the sum of the amount of:

  • Taxi out fuel, the fuel required at the departure airport for ground movement, i.e., from the gate to the takeoff runway end. It diverges from the final reserve fuel;
  • Trip fuel, the fuel required to fly from departure to destination;
  • Route reserve fuel, generally 5% of the required trip fuel quantity;

Fig. 4.7 Fuel for an altitude of 1,500 ft (457 m) to the destination

  • Alternative fuel, that is required from destination to alternate airport, except in case of island operation;
  • Final reserve fuel, which has to be enough for 30 minutes holding above an alternate airport at least (in the case of jet aircraft);
  • Additional fuel, as when required by special operations such as Extended-range Twin-engine Operation Performance Standards (ETOPS) [35]; and
  • Extra fuel, an amount that the flight dispatcher or the pilot in command seems desirable when a period longer than the planned flight time is probable because of prolonged delays or when mandatory rerouting is expected in-flight on the ground due to traffic congestion or weather deterioration.

The sum of the above quantities is called block fuel or fuel at brake release. Fuel items are mandatory by national codes. The one exception is the extra fuel, which is optional and left to the dispatcher's or pilot's discretion.

4.2.4 Notes on ETOPS and Additional Fuel

The National Aviation Authority may grant ETOPS approval to an airline operator for certain twin engine jet aircrafts, provided that the operator complies with special requirements in addition to the conventional flight conduct, including enhanced reliability, maintenance and operation of the aircraft and training, checking, licensing of its relevant flight crew and flight dispatch personnel, and the procedures they must follow [36].

The time limits 90, 120, or 180 minutes are specified in the ETOPS Approval defining the maximum distance that an aircraft can be further away from an airport. The ETOPS flight planning rules require that the whole flight path be covered by the circles drawn with ETOPS time limit radius around selected airports [37].

Those airports must meet strict requirements also for in-flight emergencies and contingencies such as engine failure or loss of cabin pressure and are called En-route Alternate Airports (ERA).

Moreover, ETOPS flight planning involves mandatory critical fuel scenario analysis for each ERA pairs and for each ERA of an ERA pair along the flight path. The aim of this analysis is to ascertain that fuel actually remaining in the tanks over a midpoint between two subsequent ERAs will be enough to reach either of the two ERAs or the original destination airport. The midpoint between two ERAs must be an Equal Time Point (ETP) [38].

That is, a point requiring equal flight time to reach any one of the two ERAs, i.e., the time to fly the distance corrected for wind effects. The analysis must consider and compute the fuel amount required for cases when both engines operate, i.e., long-range cruise and when one engine is inoperative, i.e., cruise with selected ETOPS speed. Over an ETP rapid decompression must be assumed with an emergency descent to 10,000 ft (3,050 m), than cruising on 10,000 ft up to ERA. Over the ERA a descent to 1,500 ft, i.e., 457 m and holding for 15 min follows, then a missed approach is executed after which an approach and a successful landing is made [39].

Other items in critical fuel analysis are considered for the required fuel amounts are:

  • Unreliable weather forecasts up to 5%;
  • Expected Auxiliary Power Unit consumption up to 2%;
  • Low temperatures or icing up to 1%;
  • Engine degradation up to 5% [40].

Figure 4.8 presents a critical scenario with ETP conditions considering ERA1 and ERA2.

Except for extra fuel, none of the above-mentioned fuel items are allowed to be used for purposes other than its specific role, i.e., to cover unexpected delays or reroutes. So, any time when a flight on its way ought to deviate from its original plans, a complete re-planning is mandatory. The re-plan shall ensure that the actual

Fig. 4.8 Critical fuel scenario with analysis of possible additional fuel demand

fuel on-board will cover the new trip fuel, i.e., fuel required from the diversion point to destination, the new route reserve fuel, alternate fuel, final fuel reserve, and, if applicable, the new additional fuel amount [41].

Further aspects affecting the fuel plans of airlines:

  • Applying known alternatives for route reserves, i.e., contingency, which are depending on the statistical method approved by the authorities for continuous measurement and analysis of fuel consumption by the fleet;
  • Monitoring of the engine degradation due to wear and tear by aircraft which can reveal degraded fuel efficiency in addition to performance losses. The degradation as compared to a novel engine can be expressed as a percentage and can be included in planning the required fuel quantity according to the Emission Index consideration; and
  • Assuming engine failures that occur at the most critical points of the operation.

4.3 Fuel Systems in Ships

Fuel systems in ships are used for the supply of the diesel engine. It contains the fuel system for the daily tank and the setting tank. The fuel system is processed in accordance with the performance data of the different engine manufacturers and the physical and chemical properties of fuels. The main elements of processing are storage, filtration, heating, and pressurizing [42].

4.3.1 Fuel Preparation and Fuel Supply

Sea-going ships use HFO or IFO fuels to drive the main engines at sea. MDO and MGO are high-grade fuels of low viscosity, which are used when the vessel is maneuvering.

HFO is a by-product from refining petroleum. It is warmed to 40C (104F) in the storage tanks and stored on the raised decks of the ship. This allows the fuel to

Fig. 4.9 Multistage fuel system on a ship

flow into tanks in the engine space. A part of the water and mud is already separated from the fuel in settling tanks which are heated to a temperature of approximately 70C (158F). Water and mud are regularly pumped into mud tanks [43].

Fuel is processed by separating and filtering. Oil synchronous separators are centrifuges, in which a geared wing pump thrusts the oil through a high-grade steel plate stack, turning at 12,000 rpm. The conically formed plates are equipped with separation channels. The purer and lighter oil substances flow into these channels and the heavy components, like water and dirt, are forced outside and are collected in a special waste container [44].

To optimally separate fuel, heat exchangers are in front of the synchronous separators. Their temperature is 70–99C (158–210F) depending on the fuel density. For heavy marine fuel oils with many pollutants, the separators are connected in series. The fuel filters in the marine technology are reversible flow filters. In separate modules, the HFO and IFO fuels are heated to the right injection viscosity of approximately 12 cSt at 130C (266F) at a pressure of about (7–10) 9 105 Pa, i.e., 102–145 psi or 14,620–20,885 lbf ft-2 [45].

Heavy marine fuels with high viscosity are pumped into a collection tank at a pressure of around (6–8) 9 105 Pa, i.e., 87–116 psi or 12,531–16,708 lbf ft-2 . The modern type of injection is the Common Rail technology with a pressure of (200– 300) 9 105 Pa, i.e., 2,901–4,352 psi or 417,711–626,566 lbf ft-2 . Common Rail technology is now mass produced by all marine diesel engine manufacturers [46].

Figure 4.9 shows the plan of a ship's fuel preparation and supply system containing tanks for MDO and IFO fuels, transfer pumps, setting tanks, a sample point, a counter, and a joint user [47].

In the preparation chain, foreign matter such as liquids and solids are removed from the fuel. For HFO and IFO fuels, a two-step preparation chain is necessary, while for distillate fuels such as MDO and MGO, a single-step preparation chain is sufficient. MDO and MGO are used for maneuvering in harbors or to navigate in protected sea areas. It is usually stored in MDO and MGO bunker tanks.

4.3.2 Fuel Measurement on Ships

On ships the fuel is stored in tanks, which are arranged in the double bottom. According to the IMO Convention ''Safety of Life at Sea'' (SOLAS), a minimum quantity must be stored in tanks, which are not directly endangered in case of running aground or a collision [48].

In the settling tanks, water and impurities are separated from the fuel and drained off. The level sensors in these tanks must be robust and have high durability. From the settling tank, transfer pumps move the fuel through a pre-heater to a daily tank to preheat the fuel. Temperature and pressure sensors control the process and maintain a temperature in the supply tanks which is always independent of the ambient conditions. If the fuel is too cold it must be warmed before withdrawal from the tank. The temperature of the fuel should be adjusted in the daily tank with a final pre-heater. The heat flow density is approximately 1 W cm-2 (3.413 BTU h-1 cm-2 , i.e., 22.014 BTU h-1 in-2 ) [49].

From the pre-heater, the fuel is led to a separator to purify the fuel at the second cleaning level. The surplus quantity is led back from the overflow of the daily tank into the settling tank. The level in the overflow tank is continuously monitored and attached to an alarm system. In the most cases piezoelectric sensors are used to measure the changing fuel level [50].

From the separator, the fuel enters the two daily service tanks. One tank may be used while the other is being filled. From the daily service tank the fuel is pumped to the second heater by the pressure fuel pump. From the heater the HFO and IFO fuels are passed through a viscosity meter and a regulator to the fuel filter, the flow counter, and the engine [51].

Engines or boilers, which are operated with different fuel qualities, should be equipped with a viscosity regulation via magnetic coupling. A connected electric pump saves a constant volume flow independently on fuel viscosity [52].

On modern ships, there is a flow counter in the transfer pipe which is a propeller or an oval wheel counter to determine the volume flow similar to the impeller system. The axis of the rotation must always be installed underneath the pipe axis, so that the analyzer chambers can be filled with fuel by gravity, depending upon the kind of fuel. The temperature has to be high enough to guarantee optimal flow for the continuous measurement of consumption [53].

Figure 4.10 shows the scheme of the fuel store, the pump, and the measuring system of a ship for MDO and IFO fuels [54].

Fig. 4.10 Scheme of a fuel storage, pump and measuring system

In electronically regulated pumps, impulse receivers control the operation. The feeding pump moves the fuel from the daily tank through a fine filter and a consumption measuring gauge to the mixing tank. The circulation pump moves the fuel from the mixing tank via a final pre-heater and viscosity measuring device to the injection pumps of the engine [55].

The settling tanks contain a combined overflow and bleeding pipe. The surplus fuel flows into the overflow tank, which is provided with connection to vents leading to the atmosphere. The continuous control of the volatile hydrocarbon concentration in the venting tube guarantees optimal safety; see Fig. 4.11 [56].

4.3.3 Fuel Planning on Ships

The average fuel system consists of a store, a provision, a preparation, and a supply subsystem. The common quality of these subsystems determines the rate of the fuel consumption [57].

.

Fig. 4.11 Tank with hydrocarbon control equipment

The ship must be equipped with fuel to cover its power requirement. The necessary quantity must be determined before the start of a journey by route planning based on the relations of:

$$B = \frac{b * P * S}{v} = b * P * t \tag{4.2}$$

In this equation the parameters are:

  • B the fuel needed for the journey in kg or in lb;
  • b the Specific Fuel Consumption of the engine in kg kWh-1 or in oz BTU-1
  • P the propulsion performance in kW or in BTU s-1
  • S the journey distance in nmi, mi ,or km, including drift due to wind in atmosphere and currents in water;
  • v the speed of the ship in nmi h-1 , in km h-1 or in mph; and
  • t the time of the journey in h [58].

The necessary information can be obtained from the fuel management documentation [59]. Figure 4.12 shows an example of the required fuel quantity as a function of the ship's velocity.

Fuel management provides optimal solutions to reduce fuel consumption. Merchant vessels, such as container ships, drive at a reduced speed to save fuel since the reduction of the speed from 25 to 20 knots, i.e., 46.3–37.04 km h-1 lowers consumption by about 20–25% [60]. Bulk carriers often deliver perishable goods; therefore, reducing the speed is not possible. Tankers can usually reduce speed without encountering any delivery problems. The fastest civil ships are high

Fig. 4.12 Planning the required quantity of fuel for a bulk carrier

speed ferries or hydrofoil boats. They have the highest SFC, and the highest specific exhaust gas pollution and GHG emissions.

4.3.4 CO2 Index Data Analysis

The CO2 index data analysis focuses on optimal fuel consumption. It is an entry level analysis, which identifies the main factors of voyages with unexpectedly high or low fuel consumption. The analysis is split into the individual vessels and a comparison of the fleet's fuel consumption [61].

Ideally, the CO2 index data of sister vessels are used; see Fig. 4.13.

The result of the CO2 index data analysis can be applied as input for the Operational Fuel Consumption Analysis, together with data from each ship. The experience of key crew members and the fleet management is integrated into the interactive analysis of actual fuel consumption and ranking of improvement measures.

4.4 Summary and Recommendations: Fuel System and Fuel Measurement

The global tendencies of the market for fuel products are very similar and are showing continuous growth in the price structure.

Fuel consumption can be measured in the fuel tank and in the fuel lines of the vehicles, airplanes, and ships. Dynamic fuel sensors continuously analyze the fuel flow from the tank to the engine and back from the engine to the tank.

Fig. 4.13 CO2 index analysis

The principles of the individual flow analyzing methods are different, but all current technologies are relatively expensive. Most devices measuring fuel flow are high precision micro system equipment, such as micro wings or micro turbines with rotation. Other principles are Coriolis mass flow, magnetic induction, and ultrasound technology. Further sensors use eddy current, thermal mass flow, and pressure flow.

Experiences have proven that vehicles, airplanes, and ships operate more effectively when using on-board fuel and exhaust gas management which provides data about the fuel cost per day by monitoring fuel consumption along each route and passage, combined with other important navigation information. Estimated parameters can be transferred to the fuel management center, which surveys the fuel consumed along the route. Planning and budgeting are made easier with a detailed history of the vehicles', airplanes', and ships' speed and location, direction, fuel consumption, and emissions. Using the high quality of information obtained by the system, accountants can also know the fuel prices in each tax region in time and can recommend the optimal bunker station for the crew to buy fuel.

Monitoring and managing the fuel supply reduces fuel consumption, optimizes maintenance, ensures in-time delivery, and maintains profit margins. Self diagnosis could optimally detect deteriorations caused by natural wear in the engines by the use of one fuel type and fuel mixtures or by changing the fuel.

References 77

References

  1. 80/1268/EEC: Fuel consumption of motor vehicles (16 Dec 1980), amended by 89/491/EEC (17 July 1989), 93/116/EC (17 Dec 1993), 1999/100/EC (15 Dec 1999), 2004/3/EC (11 Feb 2004)

References 79

  1. Kongsberg: Vessel performance optimizer. Cost efficient vessel operation. http://www.km. kongsberg.com/ks/web/nokbg0397.nsf/AllWeb/302A1A3175AB5D4DC12574CC0045D82A/ \$flie/KM-Vessel-performance.pdf?OpenElement

Chapter 5 Emissions

Transportation produces exhaust gas emissions. The products are gases, particles, noise, and heat. However, pollutants can be emitted not only by engines but also by other devices such as fire extinguishers, fuel tanks, and refrigerators on vehicles, airplanes, and ships. Most emissions are produced by the burning process in internal combustion engines [1].

Combustion produces several types of substances, which intensively influence the atmosphere [2]. Diesel and kerosene contain approximately 85% carbon and 15% hydrogen [3], petrol has a higher concentration of hydrogen. They theoretically burn according to the equations [4]:

$$12 \, kgC + 32 \, kgO_2 \rightarrow 44 \, kgCO_2 + 407,500 \, kJ$$ (5.1)

$$4 kgH + 32 kgO_2 \rightarrow 36 kgH_2O + 481,500 kJ.$$ (5.2)

5.1 Physical and Chemical Properties of Combustion Products

The main products of combustion are CO2 and H2O:

$$CH_4 + 2O_2 \rightarrow CO_2 + 2H_2O.$$ (5.3)

The CO2 emissions from human activities are approximately (21.00– 25.00) 9 109 t year-1 , i.e., (46.26–55.07) 9 1012 lb year-1 . Transportation emits approximately 1=3 of the whole CO2 emissions on the Earth, i.e., (8.5– 9.0) 9 109 t year-1 , i.e., (18.72–19.82) 9 1012 lb year-1 [5].

The combustion of 1.0 kg of pure carbon produces 3.67 kg, i.e., 8.10 lb of CO2. Burning 1 kg, i.e., 2.208 lb gasoline produces 2.9 kg, i.e., 6.402 lb of CO2. Burning 82 5 Emissions

1 kg diesel fuel or kerosene emits approximately 3.15 kg, i.e., 6.95 lb of CO2. Conversion from mass to volume depends on density. 1 l of gasoline produces about 2.32 kg, i.e., 5.11 lb CO2. Burning 1 l of diesel fuel or kerosene emits about 2.32 kg, i.e., 5.11 lb of CO2. 1 l of liquefied petroleum gas emits 1.8–2.0 kg, i.e., 3.96–4.41 lb CO2, depending on the proportion of C to H atoms in the fuel [6].

The fuel consumption of 5.6 l 9 (100 km)-1 , i.e., 0.305 gal mi-1 (US) or 0.41 gal mi-1 (UK) petrol results in the emission of 130 g km-1 , i.e., 4.585 oz km-1 or 7.384 oz mi-1 CO2. This is the current European level for car emissions in NEDC [7].

Burning 1 t diesel fuel or kerosene emits 1.24 t, i.e., 2 733 lb of water vapor. Emissions of H2O vapor on the Earth are much higher than the CO2 emissions, due to the large surface of the oceans but water vapor does not negatively influence the climate, with the exception of the emissions of airplanes at higher altitudes [8].

In practice, a small volume results in not completely burned end products of oxidation, such as CO and several hydrocarbon (HC) substances or oxidation products made of atmospheric nitrogen, such as NO and NO2. Substances such as CO, HC, NO, NO2, and SO2 are pollutants and dangerous to human health. They are not stable products because OH radicals change them from their intermediate state to end products in the atmosphere:

$$CO + OH \rightarrow CO_2 + H.$$ (5.4)

A modern self ignition engine combusted by diesel fuel and a jet engine combusted by kerosene produce on average 3 kg (6.6 lb) of CO per 1.0 t (2,204 lb) offuel [9]. Depending upon the type of internal combustion engine and the range of use, the value varies between 1.1 kg (2.4 lb) and 8.7 kg (19.2 lb). Global human CO emissions amount to approximately 1,077 9 106 t (2,372 9 109 lb) per year [10]. Transportation emits approximately one-fifth of the total CO amounts.

Unburned HCs are the ultimate products of combustion and can react to intermediate and later to heterocyclic aromatic organic substances, which are carcinogenic:

$$CH_4 + OH \rightarrow CH_3 + H_2O. \tag{5.5}$$

Self ignition and jet engines emit approximately 0.7 kg (1.5 lb) of unburned HCs per 1.0 t (2,204 lb) of fuel on average. The mass varies between 0.1 kg (0.22 lb) and 3.5 kg (7.7 lb) [11]. The amount of world anthropogenic HC production is approximately 275 9 106 t (606 9 109 lb) per year.

Depending on the quality of combustion, between 6 kg (13.2 lb) and 20 kg (44.1 lb), on average of 14.7 kg (32.4 lb) of NO per 1.0 t (2,204 lb) fuel is produced, mainly due to the high temperatures in the combustion zone where the nitrogen molecule dissociates and finally oxidizes [12]:

$$O_2 + N \to NO + O. \tag{5.6}$$

The annual global NOx (NO plus NO2) emissions are 195 9 106 t i.e., 430 9 109 lb. Most of them (156 9 106 t, i.e., 338 9 109 lb) are caused by

Substance Densitya Melting point Boiling point
kg m -3 (lb ft-3
)		 C (F) C (F)
Air 1.29 (0.081) -220 (-364) -191 (-312)
Oxygen 1.43 (0.089) -218 (-360) -183 (-297)
Nitrogen 1.25 (0.078) -210 (-346) -196 (-321)
Carbon dioxide 1.98 (0.124) -57 (-71) -78 (-108)
Carbon monoxide 1.25 (0.078) -199 (-326) -191 (-312)
Methane 0.72 (0.045) -183 (-297) -162 (-260)
Propane 2.00 (0.125) -182 (-296) -42 (-44)
Sulphur dioxide 2.93 (0.183) -73 (-99) -10 (14)
Steamb 0.60 (0.037) ±0 (32) +100 (212)
Hydrogen 0.09 (0.006) -258 (-432) -253 (-423)

Table 5.1 Properties of air and gaseous substances in air

human beings through industry, transport, and domestic heating. Cars and trucks emit approximately 33 9 106 t of NOx. Both, the shipping and the aviation industry individually emit about 2.5 9 106 t, i.e., 5.51 9 109 lb per year, which is commonly 5.0 9 106 t year-1 , i.e., 11.01 9 109 lb year-1 or 15% of the NOx exhaust masses caused by transportation [13].

Sulfur (S) burns with the oxygen of air and produces sulfur dioxide (SO2).

$$S + O_2 \rightarrow SO_2 \tag{5.7}$$

Anthropogenic sulfur dioxide emissions are approximately 150 9 106 t, i.e., 331 9 109 lb per year [15].

On the basis of the maximum value of the sulfur content in kerosene and gasoline, according to international standards, approximately 5 kg (11 lb) of SO2 is emitted per 1.0 t (2,204 lb) of fuel. However, in practice the emissions might be substantially lower owing to better fuel quality. SO2 causes acid rain which affects nature and also causes several diseases, and dangerous processes for human health and infrastructure [14].

Table 5.1 shows the properties of air and of gaseous components in air [16]. In both, the short- and the long-term scenarios, reducing fuel consumption and exhaust gas emissions constitute the two most important topics of transportation.

5.2 Measurement of Emissions

Definitions for emission analyzing technology are similar in all sectors of transport, i.e., road traffic, aviation, and maritime shipping. The measurement procedure and the equipment for the Type approval and the Type certification can be divided into four main groups; see Fig. 5.1.

a Normal state b 100C/212F

84 5 Emissions

Fig. 5.1 Instruments for measuring emissions in the whole life cycle of transportation

Emissions can be determined at:

  • Engine test benches;
  • Vehicle dynamometer test benches; and
  • On-board of vehicles, ships, and airplanes.

The basic method of all procedures is the examination of engine's fuel consumption and exhaust gas emission at test benches with large, registered and verified analyzers. However, fuel consumption and exhaust gas emissions of the most full size ships and airplanes cannot be tested in the same way those of road vehicles. Only small models designed from the original airplane or ship, can be placed and analyzed in flow models and wind tunnels.

On-board measurement could provide an optional way for mobile quality control. However, CO2 and pollutant emissions in exhaust gases in real operation are not continuously monitored yet, because small sensors with high durability, sensitivity, and selectivity and high speed micro controller are missing. Large, in most cases modified, compact analyzer systems can measure real emissions in experiments only for short time periods and under predetermined conditions [17].

High temperatures and pressures in the combustion chamber and changing conditions in the real environment make measurement of the concentration of exhaust gas components very complicated.

5.2.1 Measurement at Test Benches

Emissions of vehicles', ships', and airplanes' engine are usually tested at test benches. The example in Fig. 5.2 shows the analysis of exhaust gases behind a jet engine [18].

Fig. 5.2 Test bench for the control of jet engines emissions

The exhaust gas can be taken via a stainless steel gas pipe behind the engine in the exhaust gas pipe.

The measurement devices are basically the same for vehicles, airplanes, and ships.

  • Chemo Luminescence Detector (CLD) for NOx, NO, and NO2;
  • Flame Ionization Detector (FID) for HC;
  • Fourier Transformation Infra Red (FTIR) spectrometers for CO and CO2; and
  • Opacimeters, and filter-based or photo acoustic methods for smoke and particle measurements.

5.2.2 Measurement On-Board

In all means of transportation sensors are used for recording data. Sensors convert physical or chemical parameters into an electric signal on a miniature scale. The analog input signals may be steadily linear, steadily nonlinear, or repeatedly stepped. The output signals are current, tension, amplitude, frequency, etc., which are analog and can be changed to a binary digital form [19].

The common mechanical, physical, chemical, electrical, magnetic, and climatic conditions in vehicles, airplanes, and ships define the placement of sensors. Sensors must:

  • Steer, brake, and protect all operational processes if necessary;
  • Monitor the engine, transmission, undercarriage, wheels, and tires; and
  • Inform the driver or the captain of the performance, the fuel consumption, and the emissions.

86 5 Emissions

A small size and a low price are the main preconditions for the wide ranging use of sensors in transportation. There are different methods for the miniaturization of sensors and actuators [20]:

  • Combination of micro mechanical, micro electrical, and micro optical engineering production methods;
  • Utilization of uniform and flexible multibus interfaces, which is a standard application in industrial computer systems;
  • Combination of multi layer, hybrid, and semiconductor technologies;
  • Application of small measurement errors with highly developed tuner amplifiers;
  • Changing analog signals to High Frequency signals for data transfer with low hysteresis;
  • Correction of sensor deviations at the measurement site;
  • Comparison of measured values with stored basic values and compensation of the sensor signals; and
  • Storage of corrected information in the Electronic Programmable Read-Only Memory (PROM)

Temperature, pressure, speed, number of revolutions, and inclination sensors are widely used in all means of transportation. The direct analysis of combustion products is still not state of the art and is one of the hardest measurement tasks. One exception is the solid electrochemical technology for oxygen measurement. These sensors are called Lambda tubes, operate with zirconium dioxide, and optimally measure the O2 concentration in the exhaust gas in two places upstream and downstream of the catalyst. The measuring tube consists of an integrated heating element and provides the necessary operating temperature of 600C (1,112F) [21].

A changed form of Lambda sensor measures the NO concentration. Similarly designed solid electrolytic measuring cells can be used for the analysis of unburned substances such as CO and HC. Semiconductor and metallic oxide sensors do not have the required accuracy and selectivity yet.

Anemometers, and Pitot and Prandtl tubes are important elements for the air mass flow estimation in the air intake system for the combustion engine measurement technology. The first operates with a heated wire, and the second with combined pressure, sensors. The detector elements are usually installed in a Wheatstone bridge to improve the precision of the signals [22].

The measurement of the mass flow of the exhaust gas is a very complicated technology because of high temperatures and pressures, and fast changes of the physical and chemical parameters in the combustion chamber and in the exhaust gas after treatment system. The mass flow of individual combustion products in the bend pipe of the combustion chamber and in the end pipe of the exhaust gas after treatment system can be estimated only with highly complex technology to achieve the required accuracy.

5.2.3 Remote Sensing Technology

There are several optical remote sensing methods to measure the composition of exhaust gases, e.g., when flying over ships with airplanes. Laser analyzers, installed on the test airplane, measure the composition of the exhaust gas emitted from the smoke stack. These methods are very expensive and are used only in protected areas to control the ship's real emissions. Similar methods have been used at airports for analyzing the emissions of taxiing and taking-off airplanes.

The detection system measures the emissions using the absorption of laser signals from the reflected optical path. The lowest concentrations, which can be detected, are 0.5–1.0 ppm of CH4, 2.0–3.0 ppm of CO, 10.0–20.0 ppm of NO, and 0.5– 1.0 ppm of CO2. The resolution of laser operated remote sensing devices generally presents a very high quality measurement technology with clustered, coherent laser beams, not only at the test bench but under natural conditions too. Remote sensing systems cost from 20,000 to several hundred thousand Euros or US Dollars [23].

Monitoring combustion in the engines of vehicles, ships, and airplanes can be done in several phases. In the research and development phase, large, expensive, and locally fixed systems in laboratories are usually used. These devices can detect very small concentrations, provide large measuring ranges, and display extremely short-term events. They can also measure a wide range of different gases at the same time. However, the mobile application of these devices is very limited and transport of them is, in most cases, not possible.

Emissions in Road Traffic

Emissions can be determined with large analyzers on-board, if the verified equipment tested at the test bench is carried by a holding device with springs and absorption devices in cars and in duty vehicles. Despite the general feasibility, the use of certified large instruments in traffic is still very limited because of their sensitivity to vibrations, high temperatures, pressures, and soot peaks in the exhaust gas. However, certified gas analyzers produce precise results in driving for short time intervals, if their mechanical construction is very stable and cushioned and high capacity accumulators save the energy.

CO2 and NO concentrations present similar tendencies because all of these parameters are dependent on the load of the engine. In the most cases, unburned substances have an inverse or a diverged course.

An oxygen sensor in road vehicles is the state of the art and uses a uniform interface system. Others, mostly experimental systems, consist of sensors for the common analysis of HC and CO, and individual temperatures or pressures. Further systems measure engine speed, acceleration, angle of inclination, turbidity, and NO concentration in the exhaust gas. The development of further sensors still requires intensive research activity.

88 5 Emissions

Fig. 5.3 Change of emission index by wear

5.4 Emissions in Aviation

In contrast to reciprocating engines in vehicles, airplane jet engines show very gentle concentration distributions without high peaks, except during takeoff and landing phases. The mass flow is mainly dependent on the load and altitude, which correlates to the speed. The concentration of exhaust gases is usually very low, because of high dilution from the secondary air flow produces a low polluted mixture in the exhaust pipe of the engine. However, the total mass flow of pollutants and CO2 is basically high.

Measurement of combustion procedures does not belong to the typical monitoring of jet engine technology yet, although deviations in engine operation clearly lead to higher fuel consumption and higher exhaust gas emissions. Recent technology operates with analyzes for temperature, pressure, and number of revolutions. Considerations of wear and tear are based on Emission Index technology; see Fig. 5.3 [24].

Emission Index technology surveys the emission of the engine on the test bench during the certification procedure and uses statistical results of short- and longterm observation of an engine's operation.

To estimate wear and tear of the engine, exhaust gas emissions are measured at test benches and given the standardized LTO cycle represented by an engine power

-1 Cruising a is 10 650 m (34 984 ft), speed is 850 km*h (459 mi*hr ) -1 ltitude

Fig. 5.4 Comparison of average fuel consumption and emission data in takeoff and cruising of engine type A310/CF6-80

setting of 7% taxiing (26 min), 30% approaching (4 min), 85% climbing (2.2 min), and 100% takeoff (0.7 min). Outputs of HC, CO, NO, and NO2 in g kg-1 of the fuel burnt are reported together with the fuel flow. The measured emissions for all power settings are provided for a variety of engines [25].

To control air quality near airports strict directives require the continuous monitoring of pollutants' concentration with environmental measuring stations. Recent technology, uses certified measurement instruments in these stations, in the most cases designed as a measuring container [26].

Real emission rates of individual airplanes cannot be accurately estimated with ground-based measurement. They need on-board experimental technology in airplanes. Recently, databases have been created from test bench experiments on airplanes. Merely a few individual airplanes with a specific and a very complete on-board ''flying'' laboratory present realistic results concerning the fuel consumption and exhaust gas emissions in flight; see Fig. 5.4 [27].

There is the highest level of pollutants in the takeoff phase. Other phases of airplane operation at and near airports, i.e., taxiing, climbing, descenting, and landing cause less emissions. The air traffic is the origin of approximately 90% of emissions at airports; see Table 5.2 [28].

Exhaust gas emissions at airports have a special meaning for nearby residents, employees, and passengers. The measurement of individual emission sources at airports with environmental measuring stations such as measuring containers is not possible because of influencing factors in the environment.

''Driving behind'' is an uncommon experimental method where a motor vehicle with measuring instruments, and a sample tube and security plate follows the airplane on the taxiway; see Fig. 5.5 [29].

Despite the relatively small distance between the mobile analyzer in car and the airplane, the measured concentration strictly depends on the weather conditions. Experience has shown that substantially higher concentrations can be detected on calm and cold days than on sunny and windy days.

90 5 Emissions

Table 5.2 Ratio of
Table 5.2
Ratio of
emissions at airports		 Source of emissions Ratio of exhaust gas (%)
NOx HC CO
Air traffic 44 4 34
Airport worka 6 1 5
Ground traffic 3 0 3
Sum of emissions 53 5 42

a APU, Ground Power Unit, fuelling, apron, power station

Fig. 5.5 ''Driving behind'' method

5.5 Emissions in Ship Navigation

Like aviation, ship transportation belongs to the most intensively prospering branches of economy. Ships' diesel engines burn heavy fuels with low volatility. Both fuel quality and engine operating characteristics have a high effect on the exhaust gas composition and concentration; see Fig. 5.6.

However, despite similarities, the composition of exhaust gas substances and the level of emissions in ships are vastly different from other types of transportation.

MARPOL 73/78 Convention, Annex VI requires intensively decreasing emissions, similar to the EU and USA, and to other national directives [30]. Clean Shipping Index technology is gaining importance [31]. Revision of MARPOL Annex VI and the NOx Technical Code prescribes measures to decrease emissions worldwide [32]. Environmental Committees create frame conditions for the introduction of new control mechanisms [33].

The Vessel Efficiency System already contains elements of Self Diagnosis technology [34]. It can be an important measure for saving fuel and for comparing exhaust gas emissions with limiting values or time intervals which are decisive for maintaining and replacing engine components. In the future, on-board measured

Fig. 5.6 Tendencies of the exhaust gas concentrations of a supply ship while idling in harbor

CO2 emissions from ships can help determine emission trading fees and pollutant emissions can be used to calculate harbor fees, both on the basis of real emission data.

5.6 Summary and Recommendations: Emissions from Transportation

Certified large analyzers, such as Chemo Luminescent Detectors (CLD) are used at the engine test bench for the determination of the concentrations of nitrogen monoxide and nitrogen dioxide. The concentration of unburned HCs is determined using FID devices. Carbon monoxide and carbon dioxide concentrations are determined through gas absorption with FTIR spectrometer. Particle and soot emissions are measured by optical, photo acoustic, or filtering devices. This equipment is usually used in laboratories. Because of their sensitivity to vibration and their high energy demands, these devices can be applied only for short periods for mobile operations in the field.

Laser technology opens up several possibilities for remotely sensing exhaust gas emissions in transportation. The outputs of vehicles can be measured by highly 92 5 Emissions

precise laser analyzers at the edge of the road or on bridges of the highway. The exhaust gases of jet engines near and at airports and of ship engines near and in harbors can also be determined by stationary remote sensing equipment.

5.6.1 Vehicle Emissions

Exhaust gas emissions of vehicles are measured at engine test and dynamometer test benches with certified, large analyzers. Most precise instruments are sensitive to vibration, so they may be used if they can be positioned without move. Moreover, they are not suited for hard real traveling conditions during driving. Due to the high energy demand, the time interval of use in the field is limited. Micro sensors present a useful way to monitoring real operations. They always have to be combined with a micro controller system for in situ amplifying, correcting, and linearizing of measured signals.

There are two ways to lower the exhaust gas emissions of vehicles.

  • Building new transportation systems with a high technical level of on-board monitoring; and
  • Retrofitting the existing fleet with additional monitoring and regulating devices.

Retrofitting private cars is usually too expensive. However, heavy-duty vehicles could be advantageously retrofitted with adequate Self Diagnosis.

Vehicle engines have become more intelligent through the introduction of advanced micro temperature and pressure sensors in the combustion chambers. They already provide a new control quality of highly dynamically changed parameters of burning processes. The tendency will lead to the combination and the integration of sensors, actuators, and micro computer systems for sensing, acting, and data processing. Future vehicles will become intelligent tools with the highest possible efficiency for transport, information, communication, and entertainment.

5.6.2 Airplane Emissions

Since 1993, measurements of exhaust gas emissions of a single engine have been performed at the manufacturer's test facilities as part of the certification process, in compliance with requirements of ICAO international standards and recommended practices of Annex 16 to the convention of international civil aviation.

In addition to the test bench, the emissions of the airplane's engine can be measured on the airplane during idling and taxiing at the airport with help of the ''Driving behind'' method. Disadvantageously, the results depend in a great extend on weather conditions. Specific aviation measuring technology with the ''Flying behind'' method provides realistic and very precise results. However, experiments at high altitudes are dangerous and expensive.

Airplanes emit the highest amounts of NO, NO2, and particles in the takeoff phase near airports. To monitor pollutants from aircraft in this situation, the ICAO established emission measurement procedures and compliance standards for soot, measured as Smoke Number, unburned hydrocarbons, carbon monoxide, and nitrogen oxides for procedures at aircrafts. Highly precise emission analysis devices in environmental measurement containers can estimate the distribution of exhaust gas components in the atmosphere, but the allocation of peaks to individual airplanes depends on weather conditions. That is why the landing and the takeoff cycle (LTO cycles) of an airplane is defined with test bench data which provide precise conditions for comparison.

Aircraft operators can contribute to the reduction of pollutants in the exhaust gas by running and acting upon the results of an engine degradation monitoring program.

5.6.3 Ship Emissions

Monitoring the emissions of exhaust gases in the smoke stack can precisely characterize the operation of a ship's engine. Higher concentrations of exhaust gas products in comparison with the normal level can be used as recommendations for early maintenance or for engine repairs.

Near harbors, remote sensing methods can be applied to control exhaust gas emissions, but fast changing ambient air temperatures, pressure, humidity, wind speed, and wind direction often make it impossible to use the signals to create clear decisions concerning the sources of emissions, although it allows to regulate levying taxes based on exhaust gas emissions.

To reduce fuel consumption and pollutants in the atmosphere of harbors, management has to consider not only energy saving methods in the operation of ships, but also possibilities for improving the on-shore energy supply in harbors and replacing conventionally fuelled duty vehicles for logistic with environmentally friendly driven vehicles. Emissions of public and private cars, and logistic vehicles can cause a very high local concentration near parking garages and terminals at harbors. The use of alternative fuels in heavy duty vehicles, public buses, and cabs can intensively decrease emissions in harbors.

References

94 5 Emissions

Chapter 6 Electronic Systems and Computer Technology

Manufacturers of ships, airplanes, and vehicles introduced the first electronic equipment at the beginning of the 1980s. These systems have different names in road transportation, aviation, and marine transport, but they universally mean an internal system of monitoring and regulating all operation functions with electronic systems and computer technology.

Self Diagnosis is closely connected with the development of electronic technology. Electronics and computer technology opened novel possibilities for diagnosing errors and regulating optimal conditions in all vehicles, airplanes, and ships over the last few decades.

6.1 Construction of Electronic Systems

In transportation, most mechanical, physical, and chemical parameters are analog quantities. The signals are usually variable and continuous. They have to be transformed into analog electric signals, which represent information by voltage, or capacity current, etc. Analog signals can be precisely transmitted by frequency modulation from the sensor to the electronic circuit or from the electronic circuit to the actuator or to the display [1].

Historically, the analog system determined the measurement of all important physical parameters of vehicles, airplanes, and ships including engine and auxiliary devices, and the environment. The advantage of analog electronic regulators is their simplicity. The justification is mostly only carried out with potentiometers. Analog electronic systems measure, e.g., the fuel level in the tank, the humidity of the intake air, the temperature, and the pressure in the engine's combustion chamber are often placed in the cylinder head, the concentration of exhaust gas substances, such as the oxygen concentration in the exhaust pipe, etc. (see Fig. 6.1) [2].

Sensors which produce analog signals need an Analog–Digital Converter (ADC). One of the most important sensor types, the k sensor provides an analog

Fig. 6.1 Analogue control and regulation devices in a ship's engine

signal between 0 and 1.1 V. Digital systems transform continuous analog signals to discrete digital signals which represent two states, zero and a higher level one. They are more precise than analog signals and can be processed by computer controlled software. Digital circuits are usually more expensive and need a higher supply power than analog systems [3].

Digital parameters are the number of revolutions or individual positions in the engine which can be measured with impulse receivers. Digital–Analog Converters (DAC) convert digital signals to analog signals to drive electric motors or regulate actuators in vehicles, airplanes, and ships [4].

The hardware consists of electronic components on a printed circuit board equipped with analog elements, such as resistors, condensers, switchers, connectors, plugs, etc., and digital elements, such as integrated circuits and micro controllers (lC) [5].

The software is stored in the micro controller or other chips on the electronic circuit, typically in an Electrically Erasable Programmable Read-Only Memory (EEPROM) or flash memory. A micro controller is a small computer on a single integrated circuit containing a processor core, a memory and a programmable input or output peripherals. Programmable control units do not have fixed characteristics and can be reprogrammed by the user or the operator for several measures which are not essential for the basic functioning of the system [6].

In ships, digital systems may communicate text from Computer-Aided Dispatch (CAD). Digital processing, combined with the relatively narrow receiver bandwidths, provides a high quality of signal transmission with resistance to noise and fading [7].

Electronic systems secure more and more complex in all types of transportation means, i.e., in road vehicles, airplanes, and ships (see Fig. 6.2).

Fig. 6.2 Elements of a motor vehicle's electronic system

6.2 Vehicles' Electronics

In the past, fuel injection, ignition timing, idle speed, variable valve timing and valve operation etc., were directly controlled by mechanical, pneumatic and hydraulic sensors, and connected analog electronic modules. Electronics is one of the most intensively developed fields in transportation [8].

6.2.1 Electronic Control Unit

The main element of the current electronic system is the Electronic Control Unit (ECU). It is an embedded system that controls one or more of the electric and electronic systems, and the subsystems in a vehicle. Recently developed ECUs are equipped with a data logger which records all sensor signals using highly developed software in an on-board installed and operating micro controller system. Some modern vehicles have up to 80 ECUs, including engine, transmission, telephone, body, door, seat, indoor air condition, speed, convenience control units and Man–Machine Interfaces (MMI) [9].

Current ECU technology monitors many functions in vehicle systems such as:

  • The idling speed which determines the timing of the fuel injection with the crankshaft position;
  • The engine cycle which opens and closes the intake air and fuel, and exhaust gas valves;
  • The ignition which determines when the spark plugs should fire;
  • The revolution limiter which limits the highest number of revolutions allowed in the engine;
  • The cooling water temperature correction which is needed to regulate additional fuel consumption when the engine is too cold or dangerously hot;
  • Transient fuelling, i.e., a specific amount of fuel when the throttle is opened;

  • Fuel pressure modification which increases or decreases the timing of the fuel injection to compensate for a drop in fuel pressure;

  • • The first Lambda sensor signal which monitors the O2 concentrations in the exhaust gas after treatment system and modifies the fuelling to achieve a stoichiometric combustion; and

  • The exhaust gas mass at the waste gate which regulates the operation of the turbocharger [10].

Comprehensive ECU systems are essential elements in modern vehicles. Nowadays, modern vehicles cannot be built without ECU technology. Speed and course regulation, and driving stability, low consumption and emission quotas in extreme situations, are special examples of optimal management with help of intelligent electronic control systems.

6.2.2 Controller Area Network Bus

Communication chips implement the various standards which are needed to communicate with the Controller Area Network (CAN) that is often used for communication between individual devices such as the traffic indicators, the signal horn, the spark plugs, the display instruments, the monitoring light, the airbag systems, the central locking, the immobilizer, the alarm theft system, the air conditioner, the interior heating system, etc. It communicates using two wires at a speed of 500 kilobits per second [11].

6.2.3 Structure of Diagnosis

In modern vehicles, nearly all electric and electronic components in engine, transmission, steering, braking and other systems are monitored. The measured values, which are taken from sensors, are checked according to their plausibility by comparison of the individual signals with stored reference values. Moreover, all electric circuits are checked for ground defects, short circuits, and breaks in the wires.

The general ECU diagnostic functions can be grouped in:

  • Self-monitoring checks
    • Controlling the micro controller modules such as Central Processor Unit (CPU), Arithmetic Logic Unit (ALU), static and dynamic Random Access Memory (RAM), EEPROM, electronically programmable flash memory for data storage, ADC and DAC converters.
  • Periphery checks
    • Controlling the sensors and actuators for availability and functionality.
  • Communication diagnostic checks
    • Monitoring messages and signals on different communication lines.

Fig. 6.3 Electronic and computer diagnosis in vehicles

  • Plausibility checks
    • Functional monitoring all operation processes, if the detected condition could arise and uncover complex failure modes or deteriorations [12].

An appropriate error code is stored for any recognized fault, which can be designed as a warning signal in the diagnosis system (see Fig. 6.3) [13].

In addition to possible disturbances in the main engine and in the exhaust gas after treatment system, deteriorations in other components can also lead to increased fuel consumption and higher exhaust gas emissions. Optimal control and regulation needs a comprehensive electronic system.

6.3 Airplanes' Electronics

Airplanes' electronic equipment belongs to avionics. Equipment A manages communication, navigation, aircraft control, flight management, and observation of air traffic. Equipment B is installed for the control of life support, rescue, and safety. Equipment C includes the passenger seats, the luggage lags, the toilets, and the on-board kitchens. In military airplanes, this category includes the weapon fittings, the photo equipment, and the parachutes [14].

6.3.1 Flight Management Systems

Flight Management Systems (FMS) integrate diverse and independently operable aircraft electronic systems to aid the flight crew in managing the automatic pilot, optimizing in-flight performance, and monitoring fuel consumption at flight deck displays [15].

The FMS has one or more Flight Management Computers (FMC) which work with [16]:

  • Flight plan information which is set by the crew;
  • Airplane system data;
  • Performance data including airplane drag and engine characteristics, maximum and minimum speeds, and maximum and optimum altitudes. The flight crew may display these parameters on a Control Display Unit (CDU) instead of referring to a performance manual during flight; and
  • Navigation data with the database which includes nearly all information that is portrayed on conventional navigation charts. It can be depicted on navigation displays or on the CDU [17].

FMC receives fuel data from the system indicating fuel quantity and predicts performance based on the last valid fuel quantity with periodic update inputs for the estimated fuel weight that is needed to keep the current gross weight data. A message informs the crew when no update has been performed within the prescribed time or when an unexpected drop in fuel quantity is detected. The content of an automatic FMC report transmitted at pre-defined points can be a message from the ground to the FMC. Most of them require a pilot action to be accepted. However, there may be messages that are automatically loaded into the FMC.

The computer technology serves commands and information required to roll on ground, and to fly an optimum altitude and direction through climbing, cruising, and descenting. The most important commands and information are:

  • Pitch, roll, and thrust commands;
  • N1 rotation limits, N1 rotation targets, and commands to flight speed; and
  • Position data with the computed position, which is continually updated by signals from on-board radio navigation, Inertial Reference System (IRS), and Global Positioning System (GPS) depending on the airplane equipment [18, 19].

The information is passed to the Autopilot Flight Director System which includes two separate Flight Control Computers (FCC) [20]. They send control commands to their respective pitch and roll hydraulic systems. The flight control operates with two separate hydraulic systems and moves F/D command bars on the altitude indicator [21].

The Auto Throttle system (AT) provides automatic thrust control by computing the required thrust level and moving the thrust levers with servo motors which equalize thrust through the electronic engine controls while CDUs receive map and route information [22].

The pilot selects the desired information for the navigation and supervises the operating modes of the autopilot on the control display of the Electronic Flight Instrument System (EFIS) [23].

6.3.2 Engine Monitoring System

A turbofan engine consists of two mechanically independent rotors [24]. One rotor operates inside the other. The main elements are:

  • Fan;
  • Low pressure compressor;
  • Low pressure turbine installed on the inner rotor called N1 rotor; and
  • Outer rotor called N2 that holds the high pressure compressor and high pressure turbine.

The engine fuel and oil system include:

  • Valve for passing the fuel to the engine;
  • Pump to increase fuel pressure;
  • Fuel and an oil cooler and heater;
  • Fuel filter;
  • Pump to further increase fuel pressure;
  • Shut off valve before the combustion chamber; and
  • Fuel flow meter providing flow information to the FMS.

The basic parameters of the engine are:

  • N1 and N2 rotation speeds;
  • Exhaust Gas Temperature;
  • Oil pressure, oil temperature, and oil quantity;
  • Fuel flow and filter saturation;
  • Engine vibration;
  • Fuel valve position; and
  • Engine failure alert indication.

Theoretically measurement devices for combustion products and exhaust gas substances can be installed in two zones (see Fig. 6.4) [25].

Measuring parameters are indicated and displayed in the cockpit, and compared with their operating and calculated ranges.

The mechanical or electronic engine control system senses the position of the thrust lever, and compares actual and target N1 to the aircraft's configuration and altitude. It automatically sets engine thrust by adjusting the fuel flow to achieve the target N1, controlled by the auto throttle system or by the pilot.

6.3.3 Airplane Instruments

Flight instruments give information to the pilot about the aircraft's speed, direction, altitude, present position, and spatial orientation. Power plant instruments provide data about the status of the aircraft's engines and the APU. System instruments give

Fig. 6.4 Installation zones for a HC sensor in a turbofan engine

an overview of the aircraft's other systems, such as the fuel delivery, the electric subsystems, and the pressurization.

Signals can be displayed on computerized Cathode Ray Tubes (CRT) or Liquid Crystal Displays (LCD) in the cockpit [26, 27]. Pilots can monitor the status of the data link systems on the CDU monitor which gives access to maintenance personnel while the aircraft is on the ground. The flight recorder permanently records data about the flight's conditions and the airplane's operating performance.

Maintenance personnel can enter correction factors for drag and fuel flow to refine the database. The recorded data can be used for maintenance and for further statistical analysis activities.

6.4 Ships' Electronics

On-board sensors are designed to measure and transmit signals from the engine and the complementary systems to the ship's bridge and gate commands to

  • 1. charging air pressure sensor
  • 2. temperature sensor
  • 3. oil pressure sensor
  • 4. combustion sensor
  • 5. control and sensor supervision
  • 6. single control unit
    1. required value

  • I. interface

  • P. propeller

  • E. engine

  • Im. impulse receiver

  • Sw. switch

  • A. alarm

  • D. diagnosis device (OBD) interface

  • C. controlling device (OBD) interface

Fig. 6.5 Digital electronic bridge system

monitor the state of the sensors and to regulate actuators such as stepped motors, electro-magnetic and electro-mechanical valves, piezo switchers, and pneumatic and hydraulic cylinders, etc., from the bridge [28].

All electronic equipment for use on ships is constructed according to sea conditions because sea sensors and actuators can come into contact with salt water. Therefore, the casings are produced to be corrosion resistant and waterproof.

6.4.1 Integrated Bridge System

The integrated bridge is the central element for the monitoring and steering of the ship. The bridge receives inputs from various sensors, electronically displays the signals, collects positioning information, and provides regulation and steering signals required to keep the vessel on course [29].

The navigator becomes more and more a system manager interpreting the ship's movements and monitoring the vessel's performance (see Fig. 6.5).

The communication with other systems, e.g., with the fuel management system, the air conditioning, and the refrigerator monitoring system can be managed using a standardized CAN bus system. Common interface technology makes it possible to store data and follow error signals [30].

| Table 6.1 | | | | Available elements of ship electronic systems | | |-----------|--|--|--|-----------------------------------------------|--| |-----------|--|--|--|-----------------------------------------------|--|

Electronic Operation
elements
Autopilot system Autopilot collects all signals to coordinate data from many devices on the
ship, engine, and propulsion system with a common interface to keep the
vessel on a predetermined course with the optimal velocity [31]
Chart plotter Chart plotter is a high capacity electronic device for the combination of GPS
data with an Electronic Navigational Chart (ENC) to display the position
and the speed of a vessel [32]. GPS is a radio navigation system based on
space satellites that broadcast highly accurate navigation pulses to users
on the Earth
Compass Compass determines the direction of a ship relative to the Earth's magnetic
pole [33]. Modern electronic and computer supported compasses use a
series of electronic and fiber optic gyroscope sensors and connections to
GPS to locate the North
Sonar Sonar uses the movement of acoustic waves in water [34]. Electronic devices
emit pulses of sound to locate underwater objects. Reflected waves are
received and analyzed by acoustic detectors. Sonar is widely used in
military technology, in fishing, in underwater construction, and in
research field
Marine radio
system		 Marine radio system usually consists of a transmitter and a receiver, and uses
Very High Frequencies (VHF) for communication [35]. It summons
rescue services to all large ships and most small sea-going craft and
communicates with harbors, locks, and bridges on standard frequencies.
International frequencies between 156 and 174 MHz are specified for
marine applications to avoid collisions. There are two channels. The first
channel is used for emergency calls; the second channel is used for two
way wireless communication
Digital selective
calling		 Digital Selective Calling (DSC) automatically sends distress alerts without
satellites using VHF in the range from 30 to 300 MHz, High Frequency
(HF) from 3 to 30 MHz or 3,000 kHz, Medium Frequency (MF) from
300 to 3,000 kHz, and Low Frequency (LF) from 30 to 300 kHz [36]
Radar Radar is an object detection system that emits electromagnetic waves and
analyzes their interaction with objects [37]. It is able to identify the
range, the altitude, and the velocity of moving and stationary objects
such as aircraft, ships, and ground vehicles

6.4.2 Elements of Ship Electronics

There are a wide variety of marine electronics on the market (see Table 6.1).

6.4.3 Vessel Traffic Service and Automatic Identification System

The Vessel Traffic Service (VTS) is a system for identifying and locating vessels by electronically exchanging data with other nearby ships and other VTS stations [38]. It is governed by SOLAS Chapter V Regulation 12 and adapted by the International Maritime Organization (IMO).

The Automatic Identification System (AIS) is an automated tracking system used on ships and by VTS [39]. The information usually supplements marine radar and is the most important method for avoiding collisions at sea.

Information provided by AIS equipment, such as identification, position, course, and speed can be displayed on a screen or an Electronic Chart Display and Information System (ECDIS) according to the IMO requirements of the computerbased navigation [40]. Electronic communication technology displays all information from electronic navigation charts and integrates position information from the GPS and other sensors, such as radar and AIS systems [41]. Nowadays, electronic technology is not only an alternative technique to paper charts but it is more and more an essential element of navigation.

6.5 Summary and Recommendations: Electronic Systems and Computer Technology in Transportation

Vehicles, airplanes, and ships use analog and digital technology in electronic systems. The hardware consists of active and passive electronic elements. The software is usually contained in the EEPROM or the flash memory. Nowadays, electronic systems use digital micro controllers and regulate all related operation functions.

6.5.1 Electronic Technology in Vehicles

Modern vehicle technology increasingly uses electronically supported systems. In current vehicles, ECU technology controls more than 80 systems. Inspection and maintenance are becoming more intelligent, but on average more expensive, because of the increasing complexity of electronics, computers, and supporting systems. In the most cases, the repair of highly complex and multistage systems is possible only in block form.

Electronic systems are designed to control and regulate operations on-board. An engine malfunction can be recognized through the logical evaluation of individual sensor values and by the comparison of the measured signals with stored reference values.

In precisely defined checking routines, the controller device provokes brief deviations from the system status and expects a defined recognition of the change in the sensor signal. In this way, components can be checked by sensors and appropriate signals of status can be prepared by connected control devices.

Since the introduction of ECUs, manufacturers have the obligation to define malfunctions, to store disturbances, and to display them on an appropriate interface at a common level which is legally fixed.

The continuous addition of electronic features to the car electronic supply system is one of the possible factors that will lead to an increase in the system voltage in cars from the current 12 V to 42 V level.

6.5.2 Electronic Technology in Airplanes

Electronic systems are important in airplanes due to the rapid movement of the aircraft with changing weather and terrain. In contrast to road vehicle and ship navigation technique, the flight takes place in a three-dimensional space with the fourth dimension, time.

In flight pilots are faced with extremely demanding tasks to fly safely. Therefore, on-board electronic systems are designed with the primary aim of alleviating the pilot's workload and enhancing safety. Besides safety, a lot of electronic subsystems ensure optimum and cost-efficient operation to keep airlines profitable in the highly competitive air transport market.

Flight instruments give information to the pilot about the aircraft's speed, direction, altitude, and orientation. Power plant instruments provide data to the status of the aircraft's engines and the APUs. System instruments give an overview of the aircraft's other systems, such as the fuel delivery, the electric system, and the pressurization.

The continuous expansion of electronic systems on the aircraft has led to a higher demand for energy on-board, similar to road and ship energy supply technology.

6.5.3 Electronic Technology in Ships

Electronic control systems provide an excellent way to measure the effectiveness of a ship's operation, and present an independent, highly accurate means of recording and comparing the data from different engines, transmission parts, and exhaust gas after treatment modules. Electronic information systems aid in the course planning, calculating of tides, and informing the captain of the hull's condition and of the ship's speed and direction. Electronic control systems also measure the consumption of fuel to improve the vessel's performance.

The electronic monitoring of the combustion process and the composition of exhaust gases is increasingly important, not only for environmental protection, but also for lowering the costs of maintenance and repair. The supply system of ships, similar to other sectors of transportation, must provide more and more on-board power for the increasing number and energy demand of electric and electronic equipment.

Electronic and computer technology has significantly changed in the last decades. Today, captains and crews need more and more training for electronic and computer technology because of the generally increasing level of infrastructure and technology, including monitoring, steering and regulating on-board.

References 107

References

Chapter 7 Aerodynamics of Vehicles and Airplanes, and Hydrodynamics of Ships

The aerodynamics of vehicles and airplanes, and the common hydro- and aerodynamics of ships determine all events which influence the flow around vehicles, airplanes, and ships. Resistance causes draught which results from the shape of the means of transportation designed by manufacturers and is decisive for the aerodynamics of road vehicles and airplanes, and the common aero- and hydrodynamic properties of ships.

The resistance factors are called the cR and cW values and can be optimized through the body design and by streamlining.

7.1 Aerodynamics of Vehicles

The value of resistance factors are presented in Table 7.1 [1].

Individual measures like spoilers or sub-floor design do not make sense since the basic resistance depends on the aerodynamics of the vehicle body. Modern vehicle design contains aerodynamic components in an optimized form. Further improvements in the cR value are only small and the additional parts have primarily visual and less technical effects.

7.1.1 Air Resistance

There are still considerable potentials for improvement in road vehicle technology. In this sector, the improvement of the cR value by several technological measures leads to a valuable decrease in average fuel consumption from about 1 to 2% at 40 km h-1 (24.9 mi h-1 ) and from 4 to 8% at 120 km h-1 (74.6 mi h-1 ); see Fig. 7.1.

| Car design | h-1
) (mi hr-1
CR
value at the speed (km
) | | | | | | | |---------------------------|--------------------------------------------------------|----------------|----------------|-----------------|------------------|--|--| | | | 40.0
(24.8) | 80.0
(49.7) | 120.0
(74.6) | 180.0
(111.9) | | | | Optimal streamlined car | 0.15–0.20 | 0.29 | 2.3 | 8 | 18 | | | | Car with chassis covereda | 0.22–0.25 | 0.37 | 3.0 | 10 | 24 | | | | Estate car, station wagon | 0.30–0.34 | 0.52 | 4.1 | 14 | 33 | | | | Off-road vehicle | 0.35–0.50 | 0.71 | 5.5 | 19 | 44 | | | | Motor bike | 0.60–0.70 | – | – | – | – | | | | Buse | 0.60–0.70 | – | – | – | – | | | | Heavy duty vehicle | 0.80–1.50 | – | – | – | – | | |

Table 7.1 Middle air resistance value for a surface of A = 2 m2

a Reflectors and spare wheels in the trunk

Fig. 7.1 Consequences of technical changes in a mid-size car on fuel consumption

Opening headlights or the use of panorama outside mirrors increase resistance, however, these measures service the safety. In passenger car, the air resistance increases with the use of additional equipment; such as roof boxes, ski racks, roof racks, opened front and side windows [2].

Changing the aerodynamic form has clear limits. For example, if the construction of the front windshield has a too flat angle to optimize air resistance, the solar heat increases the temperature inside the car. In this case the driver needs to use air conditioning, a measure which usually negates all the positive results obtained through the saving the fuel.

7.1.2 Relation Between Speed and Fuel Consumption

The power needed to overcome air resistance grows with the square of the velocity. Therefore, slower driving to reduce air resistance is the most important measure for drivers to lower fuel consumption; see Fig. 7.2 [3].

Fig. 7.2 Fuel consumption depending on velocity

7.1.3 Rolling Resistance

The rolling resistance of tires impacts the total fuel consumption in passenger cars by approximately 10–15%. Modern commercial vehicles automatically monitor the pressure in the tires. Smooth running tires and light running oils decrease rolling resistance and lead to lower fuel consumption and exhaust gas emissions.

The rolling friction of the tires is affected by the applied construction, the used material and the internal pressure. At 20 km h-1 (12.4 mi hr-1 ), rolling resistance is nearly 100% of the external resistance acting on the car and still makes up 60% of the external resistance at 50 km h-1 (31.1 mi hr-1 ). The fuel saving rates are smaller but also similar in heavy commercial vehicles [4].

7.2 Aerodynamics of Airplanes

The aerodynamics of airplanes depends on the interaction of moving air with the surface of the aircraft [5]. The main resistance factors are:

  • Fuselage: 0.02–0.05;
  • Engine and nacelle: 0.10–0.15;
  • Tail unit with horizontal and vertical stabilizers: 0.01–0.02;
  • Wing and connecting parts: 0.2–0.3; and
  • Winglet: 0.01.

Improved aerodynamics reduces fuel consumption and thus also CO2, NO, NO2 and particle emissions. The aerodynamic drag depends on the quality of the surface, similar to vehicles and ships.

The main ways to reduce the fuel consumption of airplanes are laminar wings, laminar fins, laminar nacelles, smooth surfaces, riblet skins, wingtips, and variable

PAI - Propulsion Airframe Integration CFD - Computational Fluid Dynamics

Fig. 7.3 Main elements of airplanes with laminar flow

wing profiles regulated by high capacity micro controllers, fast sensors, and high speed actuators.

7.2.1 Laminar Flow

The drag depends particularly on the shape and on the surface of the airplane's body. Smooth laminar flow over the body produces less drag than turbulent flow. Current aircraft design generally produces turbulent flow. Slotted airfoils or actively heated, and cooled surfaces that encourage laminar flow are being explored, but their benefits still need to be proven [6].

If wing-mounted propfans and un-ducted fans are increasingly used in the future laminar flow airfoils that could tolerate the effects of propeller efflux over the wing surface also need to be developed. Alternative mounting arrangements, such as fuselage-mounted propfans may also be considered; see Fig. 7.3 [7].

Laminar flow without turbulence for wings, fuselage, stabilizers and nacelles is continuously reviewed and evaluated. Besides technology, the key consideration is the cost of laminar flow systems and their power requirements compared with savings obtained through drag reduction.

7.2.2 Nacelle Efficiency

Suboptimal integration of the engine and the nacelle which does not incorporate the air inlet can be a source of significant drag. Effective nacelle-oriented wing and tail constructions reduce turbulent flow areas [8]. The effect can be supported through the use of advanced passive flow control devices, e.g., vortex generators to

Flight systems Structure Propulsion Aerodynamics Safety
and flight deck and materials system and comfort
Fly-by-wire
On-Board
Measurement
Intelligent
navigation		 Composite
materials
for fuselage
and wing
Cast aluminum door
Integrity of
structure		 Use of prop-fan
Integration
of nacelle
and airframe
Use of un-ducted
fan engines		 Slotted cruise
airfoil
Natural
laminar
flow		 High safety for the
evacuation
of passengers
on land and water
Acceptance of
passengers
Compatibility
with airports

Table 7.2 Elements of improved airframes with advanced aerodynamics

enhance lift and advanced winglets on outboard wings. Optimal construction optimizes the lift to drag ratio by the use of sweptback or of wings with glider construction. CFD design strengthens nacelles to improve fuselage and wing surface smoothness to reduce drag.

A high bypass ratio leads to intensive turbulent air flow because large diameters have a high air resistance. On balance, high bypass ratio engines provide a significant gain for aircraft in terms of reduced fuel consumption and exhaust gas emissions.

7.2.3 Airframe Concepts with Advanced Aerodynamics

Improved aerodynamic efficiency means a higher lift to drag ratio, slotted cruise air foils and strengthened natural laminar flow [9]. New structural materials and advanced airframe systems can contribute to the improvement; see Table 7.2.

7.2.4 Wingtips and Riblets

The available width at airport gates may limit the allowable wingspan. Wingtip devices improve the efficiency of fixed wing aircraft without extending length. They reduce the aircraft's drag by altering the airflow near the wingtips; see Fig. 7.4.

Wingtips increase the efficiency of the payload of a middle range turbofan driven airplane by 500 kg (1,102.5 lb) or by a distance of 185 km (100 nmi). The saving of CO2 can reach up to 700 t i.e., 1.5 9 106 lb per airplane per annum. Wingtips also improve aircraft handling and reduce the wake turbulence hazard for the following aircraft by approximately 3% [10].

Riblets are furrows in the direction of the air flow, which are added as a film with a thickness of less than 1 mm (0.04 in) instead of paint on the surface of

Fig. 7.4 Wing of a middle distance airplane with raked wingtips

airplanes. The reduced aerodynamic resistance always leads to decreased fuel consumption and exhaust gas emissions [11]. Development of a porous surface of airplanes is a high risk technical challenge. Contamination by insects and debris can significantly reduce the performance of laminar flow and increase maintenance costs. Therefore more time is needed before it can be introduced [12].

7.3 Hydro- and Aerodynamics of Ships

The ship's fuel consumption depends on the function:

$$FC = c_R * \frac{\rho_w}{2} * v^2 * S. {(7.1)}$$

In the function cR is the resistance coefficient, qw the density of water, v the speed of the ship and S the moistened surface. The resistance coefficient cR can be relatively easily tested and exactly determined for cars and airplanes, but not for ships because ships move through both the water and the air. The resistance is the sum of both determining factors [13].

There are different basic types of approach to assess the hydrodynamic resistance:

  • Testing in a basin;
  • Testing in wind tunnels; and
  • Using a computer model [14].

Further, there are two main factors in hydrodynamic resistance:

$$c_{\rm R} = f$$ (drag and wave resistance). (7.2)

The viscous resistance or drag is related to the Reynolds number and the roughness on the hull length, and has an intensive impact on fuel consumption. Silicon-based coloring on the hull with a very low hydrodynamic resistance significantly contributes toward decreasing fuel consumption. The best example is the world's largest container ship, Emma Maersk which saves approximately 1,200 t, i.e., 2.6 9106 lb (0.01%) of fuel consumption per year through the use of silicon-based color [15].

Besides smoothness, construction factors, e.g., the form of the hull, the structure of propulsion system, and propeller also influence the resistance of the vessel. A rectangular form is usually required for high transverse stability, e.g., for tankers, and an appropriate depth of hull for longitudinal strengths in bulk carriers or container ships. If the weather is windy, the resistance of waves primarily influences fuel consumption [16]. On slow ships such as tankers and bulk carriers, which have a Froude number smaller than 0.20, predominantly the friction determines the resistance. On fast ships, such as ferries, refrigerator ships, container ships, and war ships, which have Froude numbers over 0.25, the friction is usually insignificant compared to the wave resistance [17].

In aerodynamic development in the last decades, the first improvement for fuel savings has been the enlargement of the ship's hull; the second improvement has been the regulated decrease in the ships' velocities with the introduction of automated speed control systems [18].

The interaction between hull and wave defines the choice of propulsion type in the construction phase and determines the required power of propulsion system in operation.

7.3.1 Floating on a Cushion of Air

Large ships can save energy by floating on a cushion of air [19]. This technology needs compressed air which is pumped through holes in the bottom of the ship. A ''carpet'' of air builds up beneath the hull, reducing friction as it passes through the water. The air is dispersed to either side of the propeller.

Decreasing friction between the hull and the water with an air cushion can reduce fuel consumption up to 15%. On modern ships, wave radar sensors measure the distance from the cavity ceiling to the water surface and level sensors automatically control the height of the air cushion. The heeling of the ship is also monitored, because the greater the heel angle, the higher the probability that air will escape.

Fig. 7.5 Wave output in relation to DWT on river

7.3.2 Inland Shipping

On inland water ways, construction requirements for stability and rescue equipment are adjusted to the characteristics of where the ships are going to be operating. Inland ships are smaller than sea-going ships and the resistance in shallow water plays a decisive role in engine performance, fuel consumption and exhaust gas emissions [20].

Inland ships have been constructed with an increasing load capacity over the last decades. Similar to sea-going ships, this increase in size has led to higher efficiency and to the reduction of the Specific Fuel Consumption (SCF) per DWT capacity [21].

However, there are strict limits in inland shipping. The main limiting factors are the resistance to the ground and to the river bank. Enlargement of inland container ships over 3,000 DWT usually leads to a volume of more than 5,000 m3 (176,553 ft3 ). In special cases the flow can be optimized through the installation of an additional propeller in the ship's centre. Optimal flow reduces fuel consumption, especially in the mid-speed range. Shipping up river and against the wind with high waves at wide rivers or large lakes can increase fuel consumption by up to 10% [22].

Different rotation speeds of the propeller cause turbulence between the ship's hull and the banks of the water way [23]. If the distance is too small, an increasing blocking of the feed stream to the propeller requires an increasing wave output from the engine; see Fig. 7.5 [24].

In inland freight transportation, tug boats highly efficiently push or tow a number of barges [25, 26]. The bow of a single ship should be as streamlined as possible. If a tug pushes a pre-coupled barge, the bow of the tug must be rounded by artificial designed flow plates in order to keep the turbulence at the coupling point as small as possible; see Fig. 7.6 [27].

Fig. 7.6 Wave output of an inland tug boat with a precoupled barge, depending on flow plate application

Using a long rigid-foam wedge flow plate decreases hydrodynamic resistance and wave output at the same ship's velocity by up to 10–20% [28]. Similar to seagoing ships, the inland ships' contours must be designed and kept smooth to decrease draught. A clean outer surface can decrease fuel consumption by up to 15% compared to a dirty outer surface [29]. Erosion on the outer surface of the hull can be recognized with an optical under water observation device [30].

Bow thrusters improve maneuverability and decrease fuel consumption. Transversal propulsion devices built into the bow of a ship make the ship more maneuverable. Bow thrusters make docking easier, since they allow the captain to turn the vessel to port- or starboard without using the main propulsion mechanism [31]. Stern thrusters are fitted at the stern and operate in a similar manner [32].

In inland shipping, operating near cities with high population densities, directives require an exhaust gas emission level as low as possible. That assumes the use of high quality diesel fuel. Installation, inspection, and maintenance of exhaust gas after treatment systems are playing an increasing role. Depending on the ship's course and geographical coordinates of harbors, inland ships emit pollutants near big cities. To protect environment and habitants, Self-Diagnosis system should be introduced into inland shipping first.

7.4 Summary and Recommendations: Technical Results in Aero- and Hydrodynamics

There is still a large potential for improving the aerodynamics of vehicles, airplanes and the common hydro- and aerodynamics of ships. Both aero- and hydrodynamics is generally improved by smooth surfaces and compact constructions.

7.4.1 Aerodynamics of Vehicles

There are three approaches with different reduction potentials for fuel consumption and exhaust gas emissions:

  • The use of smooth and aerodynamically optimal surfaces;
  • The introduction of new technologies to achieve low air resistance; and
  • Combining lightweight construction materials which have comparable or better surface characteristics than conventional materials such as steel and aluminum.

The power to overcome air resistance increases roughly with the cube of the speed and the energy required per unit distance is roughly proportional to the square of the speed. The power needed to overcome the rolling resistance is also a decisive factor, particularly at lower speeds and higher gross weights. At very low speeds, the dominant losses are from internal friction.

7.4.2 Aerodynamics of Airplanes

Redesigning the fuselage and the wings has the greatest potential for decreasing aerodynamic resistance. There are two main research emphases for improved aerodynamics:

  • Improvement of existing airplanes and their systems; and
  • Long-term development of completely new concepts for the next generations of commercial aircraft.

The general use of winglets can save fuel on older as well as on new aircraft because resistance goes down and fuel consumption decreases.

Radically new concepts for commercial aircraft, like a blended wing and body airplane would aerodynamically deliver substantially better lift, but there are also unsolved problems which will prevent the fulfillment of the concept in the next decades. Laminar flow can be partly realized with artificial vacuum at a very high cost level.

7.4.3 Hydrodynamics of Ships

Hydro- and aerodynamics plays a decisive role in the construction of ships and determination of operating costs, similar to other sectors of transportation. Saving fuel in ships requires:

  • In the construction phase

    • Increasing the vessel's size for higher fuel efficiency;

  • – Improving the shape of the hull's design for low aero- and hydrodynamic resistance; and

  • Fitting the engine and the propulsion system to the main construction and operation condition.

• In the operation phase:

  • Maintaining the cleanliness of the outer skin;
  • Using even and symmetrical distribution of freight; and
  • Optimizing the ship's speed and the engine's SFC.

These common measures significantly increase the hydro- and aerodynamic efficiency. Since the resistance primarily influences the flow field, the question about the optimal hull form is always connected with the propulsion, i.e., with the complete drive. Apart from the size of the ship, optimally advanced propulsion technologies can lower transport costs in operation, and consequently increase the cost competitiveness of the ship.

Also, in inland shipping, the proportions between the displacement of a ship and its power requirement improve as the ship is made larger. However, continuing development will become more and more difficult due to the limited size of inland waterways.

References

Chapter 8 Propulsion Systems

The propulsion systems generate the power and drive vehicles, airplanes, and ships. Although the operation mediums, i.e., the road surface, the air, and the water are physically and chemically very different, propulsion systems are similarly structured in all means of transportation. Parts of the propulsion are often called the transmission or drive chain.

8.1 Propulsion Elements in Road Vehicles

The propulsion system contains all assemblies which are in the drive chain between the engine and driving wheels [1]. The elements of the power propulsion are:

  • Transmission system
    • Clutch gearbox, clutch, bridge, axis, drive shaft
  • Wheels and tires
  • Steering system
    • Steering wheel, steering gearbox, rods, cruise control
  • Braking system
    • Brake master cylinder, power lines, brake disc
  • Suspension
    • Spring shock absorber, spring column.

The driving style and behavior significantly influences the propulsion efficiency.

Fig. 8.1 Influence of the gear choice on the fuel consumption in a mid-size car

8.2 Operating Functions of the Propulsion

The most important operating functions of the propulsion system are:

  • Starting and steering the vehicle;
  • Interrupting the running engine;
  • Changing the torque;
  • Adjusting the speed of the driving wheels; and
  • Operating the transmission system0 s elements [2].

Not only the engine technology, and internal and external resistances, but also the propulsion system significantly influences route fuel consumption:

$$RFC^{(1)} = f(SFC, PE^{(2)}, DR^{(3)}).$$ (8.1)

(1) RFC Route fuel consumption (2) Propulsion efficiency (3) Driving resistances There is a strong relationship between the propulsion efficiency and resistances while driving. Driving resistances mainly depend on the rolling, the air, the acceleration, the slope and the brake resistance [3].

8.2.1 Gear Choice

Independently from the gear technology, fuel consumption can be reduced by 1–3% through increasing the number of gears due to increasing the transmission ratio in the final gear because the operating point of the engine is thereby shifted towards higher efficiency.

For example with 7/8 gears instead of 6 gears in an automatic transmission, fuel

Minimal energy consumption requires careful braking and accelerating when changing gears. Since the combustion engine operates most efficiently with relatively high loads at a low number of revolutions, minimum consumption is achieved with short and strong acceleration. In cars, it is useful to switch into third gear at 25–30 km h-1 (15.5–18.6 mph), into fourth gear from 35 to 40 km h-1 (21.8–24.9 mph), and into fifth gear at approximately 50 km h-1 (31.1 mph) [5].

In compact and mid-size cars, fuel consumption can be decreased by changing from a simple manual to an automatic transmission with a suitable switching program. In the upper mid-size and full-sized cars, automatic transmissions can be best adapted to the higher efficiency of the engine.

Vehicles with spark ignition engine should always be driven with the lowest possible number of revolutions, since their efficiency depends on the load and the speed of the engine. The efficiency increases in a high gear compared to driving at the same speed in a low gear.

The automatic transmission and the adaptive driving assistance system save most of the fuel, and improve road performance and comfort, e.g., with the automatic mechanical transmission that is widely applied in heavy commercial vehicles.

8.2.2 Auxiliary Equipment

The auxiliary equipment consists of the power steering, the brake booster, the air conditioning system, the alternator, the windscreen wiper, the radio, the seat heating and the air heating etc. which are usually directly powered by the engine and significantly affect its fuel consumption.

The use of the air conditioner has the greatest effect on the fuel consumption in a mid-size car. The amount and the energy demand of equipment is rapidly rising in all means of transportation:

  • Air conditioning system increases consumption from 0.5 to 2.5 l h-1 (from 0.13 to 0.66 gal h-1 ), depending upon the manufacturer and the cooling demand;
  • Headlights increase consumption from 0.1 to 0.2 l h-1 (from 0.03 to 0.06 gal h-1 );
  • Rear window heating increases consumption from 0.1 to 0.2 l h-1 (from 0.03 to 0.06 gal h-1 ); and
  • Other electrical consumers, e.g., windshield wipers, stereo boxes, cooling boxes, electrical windows, electrically adjustable seats, etc., increase the fuel consumption from 0.2 to 0.5 l h-1 (from 0.06 to 0.13 gal h-1 ) [6].

It is predicted that the air conditioning system will remain the main source of increased consumption. Currently, it consists of a compressor directly powered by the engine, which requires a high amount of generator capacity. In the future, it may be that other solutions, e.g., the application of phase changing materials (PCM) can be used for more economical and ecological air conditioning. A few types of PCM can be produced from biomass whose use would mean basically a change to an environmentally friendly air conditioning technology [7].

Using headlights in the daylight requires a high energy demand. However, both lights are necessary for safety. Nowadays, new light emitting diode (LED) technology is reducing the electrical power requirements for the car lights [8].

Accessories need energy and contribute to fuel consumption. However, they are not considered in the measurements of the nominal consumption balance in the Type approval as determined by the NEDC. Since all these consumers use energy and lead to increased fuel consumption and exhaust gas emissions, they should be considered in the estimation of future fuel consumption [9].

8.2.3 Energy Dissipation

Propulsion in road vehicles converts the power from the engine to the tires. A chain of sub-systems can be the source of several losses [10].

A specific problem of vehicle technology is the variety of road and driving conditions. Driving in high mountains has different characteristics than driving in flat regions; or driving in arctic regions differs from travelling through a desert. Moreover, the energy dissipation in urban and in highway traffic is also very different. On city roads, the biggest energy losses arise through the internal friction of the engine and the transmission elements. In urban driving, apart from the kind of engine and fuel, the efficiency of the vehicle particularly depends on its accelerating and breaking characteristics.

The efficiency of the vehicle on the highway is largely influenced by its aerodynamics. The fuel consumption increases with the velocity to overcome air resistance and depends on the construction of the transmission elements, the aerodynamic resistance of the vehicle, and the rolling resistance of the tires.

In both urban and highway driving, the dissipation of energy in the propulsion system mainly depends on its thermal efficiency, its internal friction and the energy demand of its auxiliary equipment. The energy losses are directly characterized by the fuel consumption, which can be lowered to a minimum through suitable maintenance for lower resistances and through the use of optimal driving methods.

8.2.4 Thermal Efficiency

All losses occurring while driving, flying, and shipping are converted into heat, kinetic energy and exhaust gas emissions. Presumably, thermal efficiency can be significantly improved in the future [11]. One of the most intensive phases of fuel consumption is the ignition. In this phase, the heated air in the compression stroke must ignite the injected fuel during the combustion period. The necessary minimum ignition temperature for diesel fuel is approximately 250C (482F).

Fig. 8.2 Increased fuel consumption of a mid-size passenger car in cold weather

This temperature must be reached even with low environmental temperatures with a cold engine.

At low temperatures, the fuel consumption of internal combustion engine primarily increases with higher internal friction (see Fig. 8.2) [12].

Several measures are useful for high thermal efficiency during ignition:

  • Using a low engine speed with optimal compression;
  • Minimizing leakage losses at the piston ring between the piston and the cylinder wall;
  • Decreasing heat losses in the combustion chamber with optimal thermal insulation;
  • Applying high quality batteries to provide a high number of revolutions and high power; and
  • Using light running engine oil with low viscosity even at low temperatures.

8.3 Propulsion of Airplanes

The propulsion system of airplanes consists of the tanks, the fuel supply system, the airframe, the nacelle and the engines. Predictions estimate a decrease in fuel consumption by up to 25% with improved propulsion technology by the year 2050. Significant improvements require:

  • Improving the nacelle aerodynamics to reduce the load on the turbine and on the compressor;
  • Decreasing the size of the core engine;
  • Increasing the thermal efficiency with higher turbine entry temperatures to reduce air mass flow;
Technology scenario
Year		 Fuel efficiency LTO NOx
level
2030 20–30% better than 2010 level 10–30% below current CAEP/2
2050 40–50% better than 2010 level 50–70% below current CAEP/2

Table 8.1 Mid and long term predictions for saving fuel and decreasing emissions

  • Using heat resistant materials; and
  • Decreasing internal resistances [13].

The next generation of jet engines with a larger diameter and higher air resistance could be placed over the wing instead of under it, because of the noise, which spreads directly downward from engines placed under the wings. New turboprop and especially contra-rotating fan engines emit a large amount of noise, and endanger employees and residents near airports. However, over wing application technology must be combined with improved mechanical and aerodynamic measures, because placing the engines over the wings disadvantageously impacts the elasticity and the inertness of the wings. Furthermore, over wing construction of engines moves the load of the weight distribution upwards and thereby increases the swinging of the wings at higher velocities [14].

The most important measure is to increase the bypass ratio of the engine from 12:1 to 15:1. This measure saves fuel, and lowers the CO2 and pollutant emissions in the fan by up to 50%. The application of a contra rotating fan and a new type of combustion chamber can bring further advantages in the propulsion [15].

The long term predictions see an effective decrease in the fuel consumption and exhaust gas emissions (see Table 8.1) [16].

8.3.1 Integration of Airframe and Engine

The integration of engine and airframe would result in a reduction of the airplane's weight and the installation of specific aerodynamic elements to avoid drag.

There are complex design problems in reducing interference drag caused by flow interactions in the region of the wing pylon. Recent improvements in modeling localize airflow and bring important benefits in reduced interference drag. However, high bypass ratio engines with a higher front diameter lead to higher air resistance and therefore higher specific fuel consumption. Nonetheless, the aerodynamic disadvantages are much lower than the benefits of the new high-bypass technology.

Propulsion and airframe integration uses a large number of subsystems to manage the airplane in flight. Optimal integration of the airframe and engine allows lighter construction of the fuselage, the wing and the tail units and may contribute to a lighter undercarriage. Further system integration and extending fly-by-wire control systems offer the potential for 1–3% improvement in overall fuel efficiency including improved pollutant and noise emissions [17].

8.3.2 Retrofitting Old Engines

The incorporation of a new staged combustion system into an existing engine requires changing several parts of the engine's high pressure section including the combustor, the compressor and the outlet diffuser. In most cases, major changes in the fuel control and in the fuel supply systems are also required. Additional modifications of the turbine may be needed to accommodate changing temperatures during the retrofitted operation. The centre and the shaft sections of the old engine may be significantly different from the same engine with current combustor technology. These measures can unfortunately increase weight, maintenance costs and fuel consumption [18].

Retrofitting an older engine with one of new or advanced combustors is technically feasible, but it can involve not only the replacement of the existing combustor but also the replacement of almost all other elements of the engine core. The retrofitting could cost about 30–40% of the price of a new engine, even if it were to be done during a standard hot section overhaul. The type of the combustor chosen can affect the choice of aircraft systems and components such as the cockpit indicators, the auto throttle, the flight management computer and the interfaces [19].

In some cases, improvements of the combustion chamber and of its components should be done when building new engines.

8.3.3 Thermal Efficiency

Higher thermal efficiency can be grouped into improvements to current, simple bypass designs and to new, more complex engine constructions. The approaches include:

  • Further increases of the pressure ratio of the compression system;
  • Wide ranged use of improved hot sections with reduced or eliminated cooling requirements; and
  • Application of components with higher thermal resistance.

Making all the improvements would require substantial investments in many research and development fields, including aerodynamics, cooling technology, light weight materials, new mechanical design and optimized engine control. These common options could improve thermal efficiency by 10–20% [20].

Fig. 8.3 Several forms of propellers

8.4 Propulsion of Ships

The propulsion in a ship includes all of the elements from the engine to the propeller. The technology has been continuously and intensively changing over the last decades. Steam engines and their connected propulsion elements have been replaced by diesel engines or gas turbines. Highly developed technology is what determines the current propulsion systems. They have been improved for economic reasons and for environmental protection in the course of fulfilling the increasing level of requirements [21].

The most complex transmission systems are used in military technology in which the highest technology for fuel consumption, maintenance, redundancy, efficiency and availability is required.

8.4.1 Propeller Systems

Propellers are ceaseless flow machines which take mechanical work and pass it to the surrounding water in form of flow energy. As the trend moves toward larger ships and higher velocities, the propeller's efficiency must also be increased [22].

This requirement has led to the broad ranged application of nozzle propellers with an inflow ring. They consist of a steel ring attached in front of the propeller, which bundles the inflow of the water to the propeller and changes the flow direction [23].

Inflow rings (Mewis Duct) and higher skew increase the degree of effectiveness of the propeller and the drive performance of ships by up to 10%, primarily for large ships (see Fig. 8.3) [24].

Besides the engine, the propeller is one of the main sources of vibrations on a ship. In a lot of cases, it is necessary to change the geometry of the propeller to keep the vibrations at an endurable level for the crew and for the ship construction [25].

The number of blades in the propeller is variable. The pressure difference of the water stream in front of and behind the propeller determines the number of blades. Propellers can theoretically consist of one blade or of an unlimited number of blades. In reality, there is a practical limit to seven blades that is used on the biggest vessels such as container ships. Smaller ships have usually much fewer numbers of blades [26].

Ventilation and cavitation appear if air is vacuumed by the water surface or waste gases are vacuumed from the exhaust gas flow into the propeller, especially in fast sporting boats and in small, fast marine ships with exhaust gas end pipe at a side in the water, e.g., in stealth ships. This process reduces the performance of the propeller, and the thrust decreases. The reason for this is the decreased boiling of water if the pressure is low enough. In this case, steam formation starts at lower temperatures than 100C (212F). The high propeller speed can decrease the water pressure at the back surface of the propeller's blade and steam bubbles can appear which could cause mechanical damage. Whirls at the blades formed both in air and in water lead to perforations in the propeller's material [27].

The suitable measures against cavitation are:

  • Slow steaming; and
  • Sub-water coating.

New coatings such as finely powdered Polyamide-11 perform better than metals, including stainless steel, and have exceptional resistance to cavitation erosion [28].

Ships like tugboats and icebreakers which must have a very high thrust require a propeller with a nozzle, a large number of blades and a highly skewed design.

The Voith-Schneider propeller (VSP) can adjust the size and the direction of thrust in a broad range without changing the speed [29].

8.4.2 New Propeller Technology

Important examples of new propeller systems are:

  • Large propellers;
  • Carbon fiber propellers;
  • Pod propulsion systems;
  • Linear jets; and
  • Ring propeller driving and maneuvering systems.

8.4.2.1 Large Propellers

Large ship propellers are up to 12 m in diameter (39.3 ft) and have a weight between 80 and 120 t (176,211 and 264,317 lb). They are produced with efficient casting methods. The application field attaches large diesel engines in the range from 50,000 kW (67,114 HP) to 75,000 kW (100,671 HP). The technological parameters range from a relatively low number of revolutions between 60 and 125 rpm to a directly coupled transmission without a gearbox and with high torque.

Large propellers are usually used in very large container ships, bulk carriers and tankers as a controllable pitch propeller [30].

8.4.2.2 Carbon Fiber Propellers

Carbon fiber propellers consist of elastic carbon fiber composite material which effectively protects against cavitation. They can be used in many types of ships of all sizes. Carbon fiber propellers can be adapted to different loads with a wide range of special contours and profiles. The result is higher propeller efficiency, light weight, less vibration and less noise [31].

8.4.2.3 Pod Propulsion Systems

Pod propulsion systems are directly driven by an electric engine system. An efficient synchronous or asynchronous motor is built below the stern in a gondola which swivels all around. This ''rotating'' gondola is widely used in ice breakers, cruise ships and other large ships with a high maneuvering ability. The main thrust propeller is placed in front of the system and the auxiliary propellers are behind them [32, 33].

8.4.2.4 Linear Jets

The linear jet is a relatively new ship propulsion system which is a highly powerful technology and has a large thrust load. In addition, the noise of the propulsion is reduced. It consists of a nozzle system without a ring around the propeller. On the one side, linear jets are advantageous for high speeds of up to about 35 kn (64.8 km h-1 ). On the other side, the fuel efficiency is relatively low because of high internal resistances in the system [34].

Combinations with the Voith-Schneider propeller technology are modern development directions [35].

8.4.2.5 Ring Propeller Driving and Maneuvering Systems

Ring propellers are driving and maneuvering systems which are directly driven by an electric motor. They usually operate as a common generator and an engine with very large diameter, and are used to provide extremely high power, low speeds, and high gear torque. The advantage of the large stator and rotor diameter is the optimal maneuvering ability. The construction is mounted in a central position to safely absorb high radial and axial forces (see Table 8.2) [36].

Parameters
Size		 Engine Propeller
Wave output
kW
(BTU s-1
)		 Number of revolutions
min-1 (rpm)		 Torque
kN m
(BTU)		 Diameter
mm
(ft)		 Length
mm
(ft)		 Weight
t
(lb)
Small 3,000
(2,886)		 225 127
(120)		 3,500
(11.5)		 6,675
(21.9)		 42
(92,511)
Large 19,000
(18,026)		 130 1,396
(1,323)		 6,000
(19.7)		 13,050
(42.8)		 229
(504,405)

Table 8.2 Ring propeller systems' parameters

8.4.3 Start and Stop System

Starting and stopping put the highest load on the propulsion and have the highest fuel consumption of the engine. Ship's diesel engines are started by compressed air because no electric motor of an acceptable size would be strong enough to move the cylinders.

Before the start, the compressed air bottles and the air system are drained and the pressures are checked. Starting the engine requires a 30 bar compressed air system, i.e., 30 9 105 Pa (435 psi or 0.63 9 105 lbf ft-2 ). To start a large diesel engine, the main components must be set in motion and the first strokes of the engine with intake, compression, expansion, and exhaust must be started after the first moving of cylinders by the air pressure [37].

8.5 Summary and Recommendations: Propulsion Systems

The propulsion system is the central element of technology in means of transportation. It converts the thermal energy from the engine produced by the chemical reaction of burning in the combustion chamber, to the transmission elements. In the propulsion system thermal energy is changed to mechanical energy that drives the wheels of vehicles and the propellers of airplanes and ships.

8.5.1 Propulsion of Vehicles

The main parts of a vehicle's propulsion system are the transmission, the braking, the steering, the suspension elements, the wheel mounting, and the tires.

The effectiveness of propulsion is defined by the individual elements of the whole system. While driving, the internal and the external resistances have to be overcome by energy produced by burning of fuel in the combustion chambers.

Electronic speed regulation through the use of an automatic gear is important for optimal operation of the transmission system. Automatic start and stop systems, and starter generators can save additional fuel.

In commercial vehicles, a 42 V main power supply produces higher energy efficiency for the auxiliary components, e.g., for the heating and cooling of the propulsion system's elements [38].

8.5.2 Propulsion of Airplanes

The main elements of an airplane's propulsion are the engine, the fuel supply system, the bearing and the steering elements.

The integration of the engine and airframe results in the reduction of the airplane's weight and the installation of aerodynamic elements to avoid drag. New propulsion systems have less noise and an increase in the bypass ratio from 12:1 to 15:1. These measures save fuel and lower the CO2 emissions in the fan by up to 50%. The introduction of new turbofan and turboprop engine series depends on the economical and environmental protection requirements. The most effective measures are the use of open rotor technology, the application of contra-rotating turbines, and new types of the combustion chamber. Certification of new fuels can extend current market ranges.

Future technology will use even more intelligent and more sustainable propulsion systems with large turbofans and improved geared fans. An improvement in the future propulsion system efficiency of about 1% fuel saving per annum can be expected.

The open rotor technology burns fuel cleaner in the combustion chamber, and consumes 15% less fuel and produces 20 dB(A) less noise compared with the present systems. It can go into service approximately by 2015. By 2018, lightweight construction, integration of the engine and the nacelle, and combination of integrated airplane and engine design will decrease fuel consumption by another 20% [39].

8.5.3 Propulsion of Ships

A ship's propulsion system consists of the diesel engine, the steam or the gas turbine, the diesel electric aggregate, the direct and the indirect operating transmission elements, and the propeller.

Slower ships use a two-stroke or a four-stroke diesel engine and faster ships use gas turbines as a propulsion. Electric motors and connected transmission systems are common in submarines. Fuel cells and nuclear reactors are employed to propel some warships and icebreakers.

Fast running diesel–electric systems are gaining more and more importance, although they have a higher SFC than slow running two-stroke diesel engines. Their advantage is the wide ranged variability in the construction, the relative freedom for increasing and decreasing the number of aggregates, and the low concentration of pollutants in the exhaust gases. The construction with diesel– electric system makes it possible to optimize the external aerodynamic design and internal space construction of the ship, because they are small and systems can be decentrally placed in the hull, contrary to the high pace demand of two-stroke crosshead diesel engines.

There are many variations of propeller systems, including twin and contrarotating, variable pitch, and nozzle-style propellers. Smaller vessels tend to use a single propeller. Aircraft carriers use up to four propellers, supplemented by bowthrusters and stern-thrusters.

Apart from the number of propellers, power is transmitted from the engine to the propeller by a propeller shaft, which may or may not be connected to a gearbox. There is a growing tendency in the use of large propellers, carbon fiber strengthened plastic propellers, pod propulsion systems, linear jets, and ring propellers.

References

Chapter 9 Vehicle Engines

Internal combustion engines use fossil fuels. They determine the typical construction of transportation means by transforming the chemical energy in fuel into mechanical power. The principle is common in vehicles, airplanes, ships and portable machines (see Table 9.1) [1].

In construction machines and tractors, internal combustion engines are advantageous since they can provide a high power-to-weight ratio usually with excellent fuel energy density. Gas turbines are used where very high power is required, such as in generators in the energy industry, in jet engines of airplanes and in the auxiliary equipment of ships.

Performance standards and requirements for internal combustion engines have intensively increased over the last decades (see Fig. 9.1).

9.1 Principles of Operation

There are three basic operation principles of engine systems:

  • Internal combustion engine:
    • Two-stroke cycle with one up and one down movement for every power stroke [2]
    • Four-stroke cycle with two up-down-up-down movements for every power stroke [3]
  • Rotary engine, e.g. Wankel engine [4]
  • Continuous combustion engine which operates with the Brayton cycle [5]
    • Gas turbine, e.g. in jet engines, including turbojets, turbofans, turboprops, prop fans, ramjets, rockets, etc. They operate without separate phases, instead perform them simultaneously.

136 9 Vehicle Engines

| Table 9.1 | | | System of combustion engines | | |-----------|--|--|------------------------------|--| |-----------|--|--|------------------------------|--|

Kind of procedure Open procedure Closed procedure
Internal combustion External combustion
Combustion gas equals to working medium Combustion gas does
not equal to
working medium
Kind of combustion Cyclic combustion Continuous combustion
Ignition Self ignition Spark ignition
Kind of engine Engine Diesel Hybrid Otto Rohr Stirling Steam
Turbine – – – Gas Hot air Steam
Kind of mixture Heterogenic Homogenic Heterogenic (in continuous flame)

Fig. 9.1 Requirements for engine systems

Fig. 9.2 Basic technical variants of engines

.

Besides combustion engines, more and more electric engines are being used in transportation.

Figure 9.2 shows the technical variants of the basic principle of operation [6]. The most important vehicle types in transportation, depending on engine type, are:

  • Combustion engine vehicles (CEV);
  • Plug-in hybrid engine vehicles which are the combination of a CE and a battery or a fuel cell driven electric engine (EE);

((2.211– 2.000) 9 10-3

((1.894–1.684) 9 10-3

Injection system Nominal number of revolutions (rpm) Compression ratio (–) SFCa g (kWh)-1 (oz BTU-1 Spark ignition engines Passenger car engines with turbocharger 5,000–7,000 7–9 380–250 ((4.000–2.632) 9 10-3 HDV engines 2,500–5,000 7–9 380–270 ((4.000–2.842) 9 10-3 Self-ignition engines Cars with DI engine, turbocharger, and CACb 3,600–4,400 16–20 210–195 ((2.211–2.053) 9 10-3 HDV with DI engine, turbocharger, and CAC 1,800–2,600 16–18 225–190 ((2.369–2.000) 9 10-3 Construction machinery and farm tractors engines 1,000–3,600 16–20 280–190 ((2.948–2.000) 9 10-3 Locomotive engines 750–1,000 12–15 210–200 ((2.211–2.105) 9 10-3 Ship engines (four-stroke) 400–1,500 13–17 210–190

Table 9.2 Comparative data of spark and self ignition engines

Ship engines (two-stroke) 50–250 6–8 180–160

.

  • Full hybrid engine vehicles (FHEV); and
  • Battery driven electric motor vehicles (BEV).

9.2 Operation of Spark and Self Ignition Engines

Most vehicles are designed with a spark or a self-ignition engine. Diesel power is increasing for passenger as well as freight transportation. The main properties of spark ignition engine types are presented in Table 9.2 [7].

a SFC measured by the intake air temperature of 298 K, charging air temperature of 298 K, heating value of fuel of 11,863 kWh kg-1 , i.e., 42,707 9 103 kJ kg-1 (18,357 9 103 BTU lb-1 ) at normal conditions according to ISO 8 217:2010 and ISO 8 216-1:2010 b Charging air cooling c Cars d Direct injection e Heavy duty vehicles

138 9 Vehicle Engines

Construction Operation
Combustion chamber profile Mixture generation
Combustion chamber design Mixture regulation
Compression ratio Valve timing
Spark plug position Internal mixture creation
Ignition point Injection system
Idle stroke-bore relationship to cylinder volume Lean running

Table 9.3 Main parameters of spark ignition engines

9.2.1 Spark Ignition Engines

A spark ignition engine takes in a mixture of air and fuel and compresses it. The fuel is usually gasoline, but other hydrocarbons such as LPG or CNG are also becoming more and more common. It uses a spark plug to ignite the mixture when it is compressed by the piston head in the cylinders.

The efficiency of a spark ignition engine mainly depends on its construction and operation (see Table 9.3).

9.2.1.1 Main Construction Elements

Construction elements determine the design, the size, and the frame conditions of operations (see Table 9.4).

9.2.1.2 Main Operation Parameters

Operation modes can be regulated depending on driving conditions (see Table 9.5). Changes of operation conditions intensively impacts fuel consumption and exhaust gas emissions.

9.2.2 Self Ignition Engine

In the past, self ignition engines were generally heavier and noisier than spark ignition engines. The newest models are small and of a very similar size to a spark ignition engine in the same performance class. On the other side, self ignition engines are more efficient in fuel consumption and more powerful at lower speeds than spark ignition engines, but differences are disappearing [22].

In Europe, sophisticated cars with self-ignition engine have about a 40% share of the market. The portion in the USA and in other regions of the world is lower but it is continuously increasing [23]. Most self-ignition engines operate in road vehicles, locomotives, construction machinery, tractors, buses, and ships.

missions
mption and exhaust gas e
mpact of construction on fuel consu
I
Table 9.4

Construction parameters Physical properties
mbustion chamber profile
Co		 me. However, low cracks and piston strokes increase NOx
missions, reduces flame quenching, and the cold wall could lead to the expiration of the flame [8]
mbustion chamber can save engine volu
mpact co
A co
e
mbustion chamber design
Co		 mber of
minantly in the cylinder head in contrast to self ignition
mbustion chamber [9]. The
pistons of spark ignition engines possess either a light hollow or they are flat. In the multi valve engine an inlet
channel can be constructed as a swirl channel which can increase the mixture preparation in the lower partial-load
area especially with a low mass flow. The second channel, which operates at a higher load and higher nu
engines with direct injection, by which the piston serves for the admission into the co
mbustion chamber is predo
revolutions, serves as a filling channel [10]
In spark ignition engines, the co
mpression ratio
Co		 mit is given by the
mpression ratios. Leaner burning with a
missions. Thermal efficiency in spark ignition engines is between 0.35 and
0.45 on average and in self ignition engines between 0.50 and 0.60, depending on construction [11]
mely high in the full load range. In a spark ignition engine, the li
mely high co
missions increase with extre
mber can decrease NOx e
knocking characteristics. The NOx e
mpression ratio can be extre
higher Lambda nu
The co
Spark plug position mpulse, e.g., a variable valve
missions. Four or more valves allow the spark plug
mber of valves, and the conception of the valve i
mption and the exhaust gas e
The situation of the ignition plug, the nu
mpulse influences the fuel consu
to be centrally positioned [12]
i
Ignition point missions can be influenced by the ignition energy, and by the shape and position
mperatures, which produce favorable
mption. However, it
mizes the starting characteristics of the catalyst
conditions for post reactions of HCs and CO. Additionally, late ignition increases fuel consu
of the spark plug [13]. Late ignition points result in increasing exhaust gas te
shortens the warmup phase of the engine and opti
mption and exhaust gas e
Fuel consu
Idle stroke bore relationship to
me
cylinder volu		 mensionable, because
ment of the efficiency degree, in particular in four
mbustion chamber design, task of the construction, existing manufacturing
mption.
missions and the partial-load fuel consu
me is not freely di
However, the size of the idle stroke bore relationship to the cylinder volu
plants, etc., usually permit only a closed range for the application [14]
maller the HC and CO e
mpression ratios [15]
mprove
The long stroke engine offers a great potential for the i
mbustion chambers by higher co
The longer the stroke of an engine, the s
criteria such as the mass forces, co
valve co
missions
mption and e
mpact of operation mode on fuel consu
I
Table 9.5

Mixture preparation
ms for the preparation of
mportant
mber of revolutions per
the air and fuel mixture [16]. Selective preparation of mixtures for each cylinder of the engine makes it possible to adjust the
missions. The most i
miting factors are the load and the nu
mproved syste
mproves lean running and lowers the output of HC, CO, and NOx e
mits require i
ment protection concerning the exhaust gas li
phases are starting, i.e., the warmup period, accelerating, and braking
mal mixture in all of the cylinders of the engine. The main li
cylinder. Sequential injection i
ments for environ
Stricter require
opti
Mixture regulation ments in the mixture stability and the exhaust gas
concentration [17]. A Lambda sensor installed upstream, i.e., in the front of the catalyst, detects the air and fuel ratio and corrects
= 1 in order to achieve
m works within a very narrow range around k
mprove
A Lambda control loop regulating the fuel and air mixture offers further i
the amount of fuel for each cylinder via actuators. The syste
a high conversion ratio on the three-way catalyst
Variable valve
ming
ti		 mission, and to the increase of the torque in the low and middle range of
mproves cylinder filling
ms effectively contribute to the
m has three intake and two exhaust valves which greatly i
ming allows stable idling. Experience has proven that on-board controlled syste
mbustion, to the reduction of raw e
mber of revolutions [18]. The five valve syste
stabilization of the co
Variable valve ti
nu
Internal mixture
creation		 mely durable [19]. The biggest dangers are deposits in
mbustion
mproves the co
mal internal mixture formation with direct injection i
ms are expensive because they must be extre
missions during idling
ming, opti
ms. Besides valve ti
stability and lowers exhaust gas e
Internal mixture formation syste
the injection syste
Direct injection mpared to the intake runner
mal solutions can be achieved with multi-hole nozzles for the distribution of the air and with variation in the
missions co
mption and exhaust gas e
mpression spraying lowers fuel consu
me for the injection [20]
beginning and finishing ti
Direct injection through co
injection. Opti
Lean running missions of HCs
missions
mbling the
mbustion and low exhaust gas e
m the sequential injection of the fuel, the special design of the inlet channel for swirling and tu
%, but raw e
mbustion air to multilayered burning zones in the cylinder [21]
1. This method effectively decreases SFC by up to 15
me with a low flame speed. Stable co
mbustion ti

mber with k
mal dose of co
and CO increase because of the long co
Lean running means a Lambda nu
burning gases, and the opti
in lean engines result fro

Table 9.6 Main construction and operation parameters of self ignition engines

Construction parameters Operation parameters
Combustion chamber Valve propulsion
Cylinder block and head Mixture formation
Pistons and rings Pre-heating
Crank shaft Common Rail
Cam shaft Sealing
Con rod Cooling
Cocks Lubrication
Air and oil containing parts Torque
Fuel filter Performance
Intake air tube and exhaust gas pipe

  1. camshaft, 2. valve, 3, pistons, 4. injection system, 5. cylinder, 6. exhaust gas feed back, 7. intake pipe, 8. exhaust gas turbocharger, 9. exhaust gas tube, 10. cooling system, 11. piston road, 12. lubrication system, 13. engine block, 14. crankshaft, 15. flywheel

Fig. 9.3 Main construction elements of self ignition engines [24]

Similar to spark ignition technology, the SFC and the exhaust gas emissions of the self ignition engine depend on the construction and operation parameters (see Table 9.6).

Main construction parameters in the self-ignition engine
Table 9.7

Construction parameters Physical properties
Combustion chamber The combustion chamber is usually built as an omega hollow. An open, relatively wide design, which lies in the center of the cock, is
the most efficient form [27]
Cylinder block and head additional ripping lead to additional noise reduction [28, 29]. Complete sound enclosure is not necessary since the upper range of
In mid-sized diesel engines of up to six cylinders with ''in-line'' design, continuous mono cylinder heads which are made of
Cylinder head covers are primarily made of plastics for weight reduction. Leak tightness, flat bearing surface, light weight, and
vermicular graphite cast iron, are predominantly used [31]. Wet cylinder bushings are made of centrifugal cast iron [32]
the engine is well shielded from the driving cab with insulation mats and damping [30]
Piston and ring Future pistons, if stress will be less, can be made of aluminum [33]. Current ring technology consists of two sealing rings and one oil
wiper ring which leads to less friction and to optimal sealing behavior in the cylinder. The rings are made of specially coated steel
and cast iron. Future pistons, if stress will be less, can be made of aluminum [34]
Crank case The crank case, similar to the cylinder head, is made of vermicular graphite cast iron [35]. This material makes it possible to reduce
weight by approximately 30% and compensates the weight advantage of aluminum through higher loads and better acoustic
behavior
Crank shaft Currently, crank shafts made of micro-alloyed steel with special hardened brake spaces with high rigidity and shock mounts are used
[36]. Future multiple mounting of the crank shaft leads to smaller oscillations and thereby to reduced noise emissions
Cock divided cocks will be increasingly applied. On the strength of past experiences, the cock basement will be designed from steel in
Recently, undivided cocks are using in engine technology [37]. In the future, depending on development of material technology,
order to withstand high ignition pressures
Connecting rod New powder technologies with heat treated, sintered, and pressed light powder elements are introduced. In the long term, carbon fiber
reinforced plastics or light metal will lead to further mass reduction. Predetermined breaking points in new sintered elements will
replace the more expensive divided technology with an integrated connecting rod [38]
Air and oil containing parts 40]. Besides this technology, also double
walled sheet metal oil pans play a substantial role in special vehicles, e. g., in military vehicles
More and more oil and air containing parts are made of glass fiber reinforced plastics [39,
Fuel filter Fuel filters are made of paper and stand perpendicularly. In the future, low pressure downpipes made completely from plastics should
be installed from the tank to the high pressure pump [41]. Apart from weight reduction, this change should also lead to increased
service life without corrosion
Intake air tube and exhaust
gas pipe		 neighboring components gain in importance. Auxiliary elements in the exhaust duct are the additional exhaust gas control valve, the
compressor bypass for switching, the turbocharger, and the exhaust gate flap which supports the engine's brake. Closing the exhaust gas
Intake tubes and bend pipes are made of plastics. In order to minimize noise the interior flow is optimized by vibration-free mountings [42].
Exhaust gas ducts and bend pipes are no longer designed from cast iron but more from sheet metal [43]. The heat insulation of
flap produces back pressure in the exhaust gas which retards the engine. Braking efficiency can be improved with continuous
monitoring and regulating the flap [44]

(continued)

Main operation parameters in the self-ignition engine
Table 9.8

Operation modes
Mixture formation m 7:1 to 13:1. Diesel fuel does not
Pa (435–508 psi, i.e., 62.657–73.099 lbf ft-2) in naturally aspirating engines
mption, and the
mperatures.
mperature of up to 700–900C (1,292–1,652F) is sufficient to ignite the fuel which is
mbustion chamber te
mpression of the engine has a decisive effect on the cold start characteristics, the torque, the fuel consu
105 lbf ft-2) in charged engines [45]
produce knocking, so the engine can ignite the air and fuel mixture at high pressures and high co
m 16:1 to 24:1, and in spark ignition engines fro
9
Pa (1,160–1,595 psi, i.e., 1.67–2.30
105
9
mpressed to (30–35)
mpression in self ignition engines is fro
mbustion chamber [46]
missions. The te
mbustion air is co
105
noise and pollutant e
injected into the co
9
and to (80–110)
Physical properties
The co
The co
The co
Valve propulsion Valves are moved by the camshaft. Conventional camshafts are made of steel and used to regulate the valves [47]. Valves are usually
m has two inlet and
regulation of the valves could be replaced with electronic regulation. However, in the distant future, variable valve regulation in
mal gas exchange and cylinder filling. In the near future, the mechanical camshaft
ment of the injection nozzle. A four valve syste
ms will make the camshaft redundant
m two metals and a central, perpendicular arrange
two exhaust valves which produce opti
mmon Rail syste
mbination with Co
made fro
co
Preheating of fuel and
air		 missions, especially during cold starts. In very cold weather,
mportant for reducing exhaust gas e
additional burners are necessary [48]
Preheating the fuel and air is i
mmon Rail
Co		 m should use a lower pressure than in the
105 lbf ft-2). However, tendencies show in the direction of higher
mps should be used for higher efficiency, longer life span, lower weight, and
105 lbf ft-2). Specific
9
Pa (14,505 psi, i.e., 20.89
mbustion syste
mperatures in the co
105
9
mps use pressures above 1,000
9
Pa (11,604 psi, i.e., 16.71
pressures and lower drop diameters. Radial piston pu
applications that must be protected against high te
105
mmon Rail injection pu
9
mately 800
reduced noise [49]
past by approxi
Current Co
m
Sealing syste		 Cylinder head sealing must be adapted to the increasing pressures [50]. The materials of the cylinder head define their use, which
Wave can be sealed with radial sealing. Crankshaft seals have to cope with high
greatly influences the life span of the engine.
mperatures
pressures and te
m
Cooling syste		 mperature is regulated by ambient air. Today, cooling fans with a
mportant because large
W (20 and 28
Wet cylinder barrels and bored or
mperatures and therefore they must be intensively cooled
mmercial motor vehicles use a high proportion of the engine power, between 15 and 21 k
mperature. The precise regulation is i
ms [51].
mperature of the self ignition engine is regulated by two different cooling syste
special coupling are used which turn on in response to the engine te
calibrated ducts are used for interior engine cooling. Engine te
mbustion te
HP). Future engines will work with higher co
fans in modern heavy co
The te
(continued)
Table 9.8
Operation modes Physical properties
m
Lubrication syste		 mption of
which equals to 0.53–0.78 gal (1,000 km)-1, i.e., 0.85–1.30 gal (1,000 mi)-1. Oil should be changed after 30,000–
ms lubricate the whole
me lubricating oil at the rate of 2–3 l
engine, meaning the crankshaft, the piston rod, the camshaft, the valves and the nozzles, the turbocharger, etc. Consu
mption. Pressure lubrication syste
lubricating oil depends on the load. Oil must be changed because it ages. Heavy trucks consu
Lubrication reduces the internal friction of engines and affects the fuel consu
60,000 km, i.e., 18,630–37,260 mi [52]
(1,000 km)-1
Torque mber of revolutions of
% by
The force of the expanding air and fuel mixture which drives the piston together with the lever arm of the crankshaft downward is
m;
self ignition engines has been substantially increased since the beginning of the 1990s. Now car engines run up to 5,500 rp
mption by much as 5
mparison with traditional oils [53]
converted into torque [54]. The torque depends on the average piston speed and operating pressure. The nu
Synthetic engine oils with low viscosity may be slightly more expensive, but they can cut fuel consu
reducing the internal friction of the engine, particularly in cold starts in co
Performance me interval. It increases with higher torque and higher
ms with electronic speed regulation, e.g., an Electronic Diesel
W (109 HP) and
m. Modern self ignition engines of vans with fuel injection operate in a performance range between 80 k
The performance depends on the output, which is generated as a power per ti
mooth ride [55]
m. Future injection syste
Control (EDC) will deliver high engine torque with a s
heavy-duty vehicles usually run at lower rp
W (136 HP) [56]
100 k
rp

Fig. 9.4 Cooling and lubricating system of self ignition combustion engines

9.2.2.1 Main Construction Elements

Self ignition engines are usually built in a design with ''in-line'' and ''V'' engine form [25]. Friction losses in the construction are shared in the transmission by 32%, in the oil pump by 10%, in the valves by 8%, and in the piston rings by approximately 50%.

Figure 9.3 presents the main elements of a self ignition engine [26].

The main construction elements and their influence on fuel combustion and exhaust gas emissions are presented in Table 9.7.

9.2.2.2 Main Operation Parameters

Table 9.8 presents the impact of main operation modes on the fuel consumption and exhaust gas emissions of self ignition engines.

Figure 9.4 shows the common operation of cooling and lubricating system of self ignition engines.

9.3 Summary and Recommendations: Vehicle Engine Technology

There are four- and two-stroke engines. The combustion cycle of four-stroke engines consists of the intake, the compression, the expansion, and the exhaust. A complete operating cycle of the engine requires two crankshaft revolutions. Four-stroke engines have one inlet and one outlet valve per cylinder for the gas exchange.

Key parts of the four-stroke engine are the crankshaft, the connecting rod, one or more camshafts and the valves.

In a two-stroke engine, two piston strokes and only one crankshaft revolution are needed for one combustion cycle. The first cycle covers the intake and the compression; the second cycle does the expansion and moves the exhaust gases 146 9 Vehicle Engines

from the combustion process. The intake and the exhaust of the combustion gasses can be moved only by the motion of the piston because of high flow inertness.

Two-stroke engines require other forces such as an extra pressure gradient produced by a flushing blower which flushes the cylinder from the air intake to the exhaust gas side. In four-stroke spark ignition engines, the blower can be an internal system which is constructed by the crankcase volume change; in twostroke self-ignition engines, an external device, e.g., a Roots supercharger is used for positive displacement [57].

There are still potential for improvement both for the spark and the self ignition engine.

References

References 147

  1. Friction loss analysis of combustion engine parts. http://www.iae.fme.vutbr.cz/frictionloss-analysis-of-combustion-engine-parts

Chapter 10 Airplane Engines

Aircraft engines operate with reciprocating, i.e. a four-stroke internal combustion engines or with gas turbines. Gas turbines, operating continuously and using the principle of the Brayton-cycle, have gained a leading position in the last 50 years. Most modern airliners use gas turbines in jet engines, fly faster and at higher altitudes than reciprocating engine and propeller driven airplanes [1].

The thrust depends on the mass of air moved, mixed with the exhaust gas in the core and with the air in the by-pass. Propellers and gas turbines' blades are flow machines to move airplanes, similarly to ships in water, through rotating and creating thrust in the air. Propeller engines have higher efficiency and lower fuel consumption than jet engines since they move a large air mass at a slower speed in opposite to jet engines which move a small air mass flow at high speed.

The gas turbine in a modern jet engine produces usually low concentrations of pollutants in the combustion chamber (see Fig. 10.1) [2].

However, the real proportions are very different in airplanes depending on type, age, and maintenance of airplanes. Beside the high efficiency and the low concentration level, the general problems arise from the high mass flow of burning substances and the high altitude of the emissions. Cold temperatures and low density of ambient air in higher altitudes lead to long decomposition time intervals of the substances emitted [3].

10.1 Types of Engines

The most important types of aircraft engines are the turbojet, the turboprop, the turbofan and the turboshaft engine type. Turbojet is the oldest kind of general purpose jet engine. Currently, the most important system is the turbofan technology. The main parameters of types are presented in Table 10.1.

150 10 Airplane Engines

Fig. 10.1 Exhaust gas components of a turbofan engine in flight

Table 10.1 Characteristics of turbojet, turbofan, and turboshaft engines

Characteristics Description
Turbojets Turbojets consist of an air inlet, an air compressor, a combustion chamber, a gas
turbine and a nozzle [4]. The air is compressed into the chamber, and heated
and expanded by the combustion. Turbojets can be made more fuel efficient
by raising the BPR which is the combustor inlet pressure divided by the
intake pressure modified by the turbine temperature
Turbofans Turbofan engines are designed to produce additional thrust by diverting a
secondary airflow around the combustion chamber [5]. The secondary airflow
bypasses the engine core and mixes with the faster stream from the core. BPR
in turbofan engines means a factor higher than 2.5. The bypass air generates
increased thrust, cools the engine and aids in suppressing exhaust noise.
Turbofans have a higher exhaust gas speed than turbojets and are more
efficient at subsonic speeds up to roughly Mach 1.6
Turboshaft The turboshaft is similarly designed to the turboprop engine [6]. The shaft is
connected to a transmission system that drives helicopter rotor blades,
electrical generators, compressors and pumps

Combinations of gas turbine and propeller have a high efficiency [7]. Thermal efficiency can be increased by minimizing heat losses. Consequently, net thrust will increase, while SFC, i.e., fuel flow per net thrust decreases. Currently, improved combustion chamber design, highly resistant turbine materials, and an optimal vane and blade cooling are required to cope with higher temperatures in the combustion chamber and in the turbine inlet. The best SFC values are reached by contra-rotating, unducted turbofan engines [8].

Turbofans optimally operate in the range from 400 to 2,000 km h-1 (from 250 to 1,300 mph) depending on the net thrust and the intake air flow. They are classified into two categories:

  • Low bypass ratio; and
  • High bypass ratio.

In a low bypass turbofan, only a small amount of air passes through the fan ducts. The fan has a small diameter. The low bypass turbofan is always constructed in a very compact form. In high bypass turbofans the fan is larger to force a higher volume of air through the ducts; the thrust is greater, and the thrust specific consumption is lower than in low bypass turbofans [9].

Technical parameters of modern jet engines
Table 10.2

| 34.5:1
35.5:1
41.6:1
42.8:1
34.8:1
42.0:1
38.5:1
36.1:1
47.7:1
41.4:1
OPRb
By-pass ratio
10.4:1
4.3:1
5.0:1
5.8:1
5.8:1
5.3:1
7.1:1
8.7:1
8.7:1
9.2:1
(10.68)
(7.19)
(8.11)
(9.16)
(9.40)
(7.99)
(9.66)
(9.72)
(9.33)
(9.25)
2.192
2.474
2.794
2.868
2.438
3.256
2.946
2.964
2.845
2.822
Fana
(ft)
m
Boeing 747–400, 767–300
–200LR, Freighter
Boeing777-300ER
Airbus A380–800
Airbus A380–800
Boeing 787–8
Boeing 787–8
Airbus A330
Airbus A330
Boeing 777
Boeing 777
Use
(115,552)
(60,609)
(71,107)
(95,005)
(97,995)
(71,999)
(70,006)
(69,968)
(63,756)
(63,792)
269.60
316.30
422.60
435.90
320.27
514.00
311.40
311.23
283.60
283.76
Thrust
(lbf)
kN
Rolls-Royce Trent 1000-A1
Rolls-Royce RB211-524H
GE Aviation Genx-1B64
Rolls-Royce Trent 772
Rolls-Royce Trent 895
Rolls-Royce Trent 970
Engine Alliance
A3
GE Aviation
GE90-115B
Parameter
CF6-80E1
W4098
GP7270
Engine
P | Technical parameters of modern jet engines
Table 10.2 | | | | | |-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------|--|--|----------|-------------| | | | | | Mc
D | CFd | | | | | | kg | | | | | | | (lb) | | | | | | | 4,386 | Nov. 1989 | | | | | | (9,671) | | | | | | | 4,748 | Jan. 1994 | | | | | | (10,469) | (Trent 700) | | | | | | 5,942 | June | | | | | | (13,102) | 1999 | | | | | | 7,484 | Aug. 1999 | | | | | | (16,502) | | | | | | | 5,091 | June | | | | | | (11,226) | 2001 | | | | | | 8,761 | July | | | | | | (19,318) | 2003 | | | | | | 6,436 | Nov. 2004 | | | | | | (14,191) | | | | | | | 6,085 | Jan. | | | | | | (13,417) | 2006 | | | | | | 5,409 | Aug. 2007 | | | | | | (11,927) | | | | | | | 5,816 | March 2008 | | | | | | (12,824) | |

Diameter b Overall Pressure Ration, which means the pressure ratio between the front and the rear of the gas turbine engine's compressor. Higher OPR implies higher efficiency, but the weight of the engine increases. c Dry mass d Certification

152 10 Airplane Engines

  • 1. diffusor channel between compressor and combustion chamber
  • 2. division of the air throughput into primary and secondary air
    1. mixing and gasification zone
    1. combustion zone
    1. thinning zone
    1. smoothing of the flow in the combustion chamber`s exhaust zone

Fig. 10.2 Main elements of a jet engine's combustion chamber

10.2 Fuel Consumption and Thrust

Development is moving toward higher bypass ratios, larger fan diameters, higher masses, higher thrusts, and lower fuel consumption rates.

Currently, thrust and speed are presenting continuously increasing and SFC decreasing tendencies in aviation (see Table 10.2) [10].

The production costs of jet engines are increasing. The price range of modern turbofan engines is from €10 to 30 million, i.e., from US \$14.3 to 43.9 million.

Increasing the bypass and pressure ratio without increasing the fan diameter means less core flow which increases the temperature at the turbine inlet [11, 12]. The control of the combustion chamber needs additional micro sensors for burning and exhaust gas products. Self-Diagnosis will become more important since modern jet engines are constructed with higher loads and higher durability.

10.3 Construction of the Combustion Chamber

In the combustion chamber the burning process produces high pressures and high temperatures according to the mixture conditions. Most combustion chambers operate with an air surplus in the burner can [13]. The mixture in the combustion zone can be influenced by the fuel to air relationship, i.e., the Lambda number. At lower engine speeds, the relationship is approximately k = 1.3, while cruising the mixture has a Lambda number of around k = 1.6. The mixture of fuel and air and the combustion process in a single combustion chamber are illustrated in Fig. 10.2 [14].

The main combustion chamber type is the ring combustor. The compressor pushes the air flow to the combustion chamber at a speed of approximately 150 m s-1 (335.61 mph), in which the kerosene and air mixture has a combustion speed between 25 and 30 m s-1 (55.93 and 67.12 mph). For efficient combustion, the fuel and air mixture must remain in the combustion zone from 0.004 to 0.008 s. This time interval is long enough to completely burn the fuel. The fuel drops must be gasified, mixed with air, and heated to the ignition temperature. The combustion temperature in the burning zone is approximately 2,573C (4,663F) [15].

Higher temperature and pressure increases the damage in the combustion chamber which requires more maintenance and repairs. Therefore, improved cooling technology in the combustion chamber and in the exhaust gas pipe are required which contributes to higher efficiency and to lower costs [16].

The optimal operation of the combustion chamber of a jet engine's gas turbine must work with:

  • Stable, vibration-free combustion process on the ground and in the air;
  • Optimal thinning of the combustion gases at a temperature which does not lead to overheating of the first turbine stage;
  • Efficient burning fuel and efficient releasing the energy contained in the fuel;
  • Low pressure loss which could be the result of increased friction;
  • Simple maintenance and repair; and
  • High durability of all elements [17].

These facts are the preconditions for optimal operation and must be inspected and maintained during the whole life time of the engine.

In the future, the following goals will be more important for the further development of combustion chamber technology:

  • Improving the construction between the compressor and the turbine to save space and weight;
  • Maintaining a more uniform temperature and pressure distribution in the exhaust cross-section; and
  • Optimizing ignition [18].

10.4 Emissions from the Combustion Chamber

In aviation, the level of unburned CO and HC from engines is very low and the amount of visible smoke is under control currently. The exhaust gases contain more CO and HC only during idling because of the low air and fuel throughput, the 154 10 Airplane Engines

Fig. 10.3 Emissions of pollutants from a gas turbine

low pressure and the low temperature in the combustion chamber which leads to the production of unburned substances (see Fig. 10.3) [19].

The Bypass Pressure Ratio (BPR) means the rate of air mass flow between the engine bypass and the engine core. Increasing the BPR has limits in turbofans because higher temperatures at the turbine rotor and compressor inlet produce material problems [20]. In this section, improved vane and blade cooling and high efficient compressors with heat resistant materials, e.g., plasma spray ceramic protective layers and thermal barrier coatings on the surface (ZrO2Y2O3), are still needed [21].

10.5 Measurement in Turbofan Engines

Turbofans contain two mechanically independent rotors, one inside the other. The fan, the low pressure compressor and the low pressure turbine are installed on the inner rotor, called the N1 rotor. The outer rotor, called N2, holds the high pressure compressor and turbine. It includes an intake valve to pass fuel to the engine, a pump to increase fuel pressure, coolers, heaters and filters for the fuel, a second pump to further raise the fuel pressure, a shut-off valve in front of the combustion chamber and a fuel flow meter providing flow information to FMS.

Turbofans contain tubes for analyzing rotation speeds N1 and N2, Exhaust Gas Temperature (EGT), fuel pressure, fuel temperature and fuel flow in the pipes, fuel quantity in the tanks and filter saturation. The electronic engine control senses the position of the thrust lever, compares the actual with the target N1. According to the aircraft configuration and altitude, it automatically sets the engine thrust by adjusting the fuel flow to achieve the target N1, commanded by the auto throttle system or by the pilot.

Measuring points in the combustion and exhaust gas system are presented in Fig. 10.4.

  • 1. spiner cone
  • 2. Low Pressure Compressor (LPC) containing 4 grades
  • 3. Variable Bypass Valves (VBV) containing 12 valves
    1. High Pressure Compressor and Variable Stator Vanes (HPC and VSV)
    1. thrust reverser
    1. combustion chamber
    1. High Pressure Turbine and Low Pressure Turbine (HPT and LPT)

Fig. 10.4 Temperature and pressure at the main measuring points in the engine type CF6-50 E/C 2

Table 10.3 Main operation parameters of the engine type CF6-80C2B1F

Parameters Values
Total thrust 226.85 kN (51,000 lbf)
Fuel flow 9,300 kp h-1 (660,905
pdl h-1
)
RPM N1 fan speed 3,433 (100%)
RPM N2 core speed 9,827 (100%)
Air flow 685 kg s-1 (1,510
lb s-1
)
Fan air flow 558 kg s-1 (1,230
lb s-1
)
Prim air flow 127 kg s-1 (280
lb s-1
)
Bypass ratio 4.4:1
Compression-ratio 29.4:1
EGT 887C (1,629F) (max 950C
(1,712F) up to 2 min)
Turbine inlet temperature 1,400C (2,552F)

Table 10.3 shows the main operation parameters. Fuel flow in engines of the 1990s has been approximately 2.5–2.6 kg s-1 (5.5–5.7 lb) [22]. The ratio of fuel flow in jet engines has been continuously decreasing in the last years. Modern engines consume less than 2.0 kg s-1 (4.4 lb s-1 ) of fuel. The TSFC attaches ranges from approximately 17.1 g (kN s)-1 , i.e., 0.605 lb (lbf h)-1 to 8.696 g (kN s)-1 , i.e., 0.307 lb (lbf h)-1 .

156 10 Airplane Engines

10.6 Summary and Recommendations: Combustion Process in a Jet Engine

The first fuel-efficient engines with higher bypass ratios were introduced in the 1970s and 1980s. They reduced HC and CO emissions but increased the NO and NO2 output. In contrast to unburned substances, NO and NO2 concentrations are higher in full load intervals because of the higher air and fuel throughput, and the higher pressure and temperature. The aim is to reduce NO and NO2 levels by 50% of the current level within 5–10 years.

The new approach involves improving the uniformity of fuel injection, mixing fuel and air, and reducing emissions. NOx levels may be reduced to 50–70% of the present amount by using multiple combustion zones in radial and axial configurations, which permit optimal local temperatures and burning times in the combustor.

High bypass turbofan engines are generally quieter than the earlier low bypass engines. Using multi-stage fans significantly increases thrust and velocity of exhaust gases. The combination of a higher BPR and a higher turbine inlet temperature further improves thermal efficiency and lowers SFC.

Both economic and safety considerations limit the installation of new combustor designs to old engines. A new construction is often introduced as a package that includes modifications to the combustion chamber, to the fuel nozzles, and to the engine control. Positive steps must prevent intermixing of new and old components during maintenance. Of course, other requirements such as better fuel consumption, lower peak cycle temperatures, reduced NO, NO2, and particle emissions, and high durability with low costs must also be balanced if combustion technology is retrofitted.

Micro sensors in the combustion chamber could become important in the future jet engine technology because they could add additional signals to the current sensor technology and control the first deteriorations in the burning process. Self Diagnosis can be a further developed stage in addition to recent Emission Index technology.

References

References 157

  1. Schubgiganten Top 10 (2010) Flugrevue. Das Luft- und Raumfahrtmagazin. pp 82–87. ISSN: 0015-4547. http://www.flugrevue.de

Chapter 11 Marine Diesel Engines

Marine diesel engines are very similar to the self-ignition engines in heavy-duty vehicles, but they are generally larger, more complex, and operate with higher efficiency. About 75% of all marine diesel engines are four-stroke engines; however, 75% of the installed power is produced by two-stroke engines. Four-stroke marine diesel engines are gaining importance not only in inland, but also in marine shipping, primarily in smaller container and bulk carrier ships. Fuel consumption and exhaust gas emissions of ship engines depend not only on the principle of operation, but also on the type, the size, the power, the load, the speed, etc. [1].

On the one side, fuel saving and exhaust gas after treatment technology in shipping will gain more importance in the next years because fleet management will focus on fuel and exhaust gas emission saving. On the other side, fuel saving is directly combined with environment and climate protection. Higher costs of fuel intensively support developing fuel saving technologies. Fuel saving also contributes to innovations in climate protection technology and to development in legislation [2].

11.1 Fuel Consumption in Marine Diesel Engines

Modern marine diesel engines with direct injection have a maximum brake efficiency of 40–43%. Further improvement of the direct injection technology is possible. Although improvements will continuously go on, they will be carried out in small steps.

Retrofitting older engines has often high costs, particularly in larger ships. This is one of the reasons why quality of retrofitting measures must always have a high level. The attempts to improve engines include:

• Controlling and reducing the friction of the main and auxiliary parts with lubrication;

Fig. 11.1 SFC of a medium speed marine diesel engine in fuel consumption diagram

  • Reducing the heat losses of the cylinder walls by optimizing the thermal insulation of all heat parts, particularly near the cylinders;
  • Introducing variable swirl with the injection of the fuel;
  • Using variable intake air flow;
  • Introducing a variable compression ratio using specific high dynamic pressure and temperature sensor and actuator technology;
  • Using SCR catalyst and particle filters in the exhaust gas after treatment system additionally to recent silencer technology and occasionally in addition to the exhaust gas boiler technology; and
  • Applying gas concentration and particle sensors to monitor the catalyst and the particle filter [3].

All parts of the engine, the turbocharger, the compressor and the exhaust gas after treatment system must be optimized to reduce fuel consumption and emissions. The use of electric turbochargers is possible, but electric motors are great and have disadvantageous high inertia when starting.

The SFC firstly depends on the number of revolutions and the exhaust gas pressure. The piston-stroke to bore ratio, the size and the form of the valve cross section and the valve timing additionally influences the SFC [4].

The SFC can be estimated, depending on the number of revolutions and the Break Mean Effective Pressure (BMEP), with fuel consumption diagrams drawn on paper or on computer (see Fig. 11.1) [5].

Changes in the SFC can be exactly measured with analyzing CO2, unburned hydrocarbons and carbon monoxide concentrations in the exhaust gas. The preconditions for successful analysis are suitable micro measurement devices applicable in ships, which can analyze the concentration with the required accuracy and durability [6].

Table 11.1 Characteristics of large, slow speed, two stroke marine diesel engine

Engine
characteristics		 Physical properties
Operation
parameters		 Two-stroke crosshead engines have piston diameters from 350 mm (13.82 in)
to 1,080 mm (42.66 in) and strokes of up to 3,200 mm (126.4 in). The
average cylinder volume is 600–650 l (21.2–23.0 ft3
) with a middle
cylinder bore of 600 mm (23.6 in). The piston speed is between 4.0 m s-1
and 6.0 m s-1
, i.e. between 13.2 and 19.7 ft s-1
. Fast engines run at about
8.0 m s-1 (26.2
ft s-1
). The ignition pressure ranges from 140 9 105 Pa
to 160 9 105 Pa,
i.e., from 2.92 9 105 lbf
ft-2 to
3.34 9 105 lbf
ft-2 or
from 2,030 to 2,320 psi [9]
Dimensions Currently, the dimensions are up to 29 9 15.5 9 11.5 m or 95.1 9 50.8 9
37.7 ft, i.e., length x width x height and the weight is up to 2,300 t
(5,066,079 lb) (Wärtsila 14RT-flex96C). The wave output ranges up to
84,420 kW (114 811 HP), (Wärtsila RT-flex/RTA96C) at 102 rpm.
However, development is very fast and new engines will be larger and
heavier [10]
Control system Fully electronic engine control makes it possible to separately regulate the
fuel injection, the exhaust-valve opening and closing, the cylinder
lubrication and the compressed air starting the engine operation after
interruption. Sensors monitor pressures, temperatures, number of
revolutions and other fuel management parameters, such as fuel
consumption [11]
Fuel Two-stroke marine diesel engines can burn a variety of fuels, even biogenic
and synthetic fuels or CNG and hydrogen [12]
Efficiency The two-stroke engine theoretically would produce twice the power of an
equal sized four-stroke engine. However, due to losses from the lower
operating efficiency only approximately 60% of the theoretical efficiency
can be reached. Two-stroke engines guarantee low fuel consumption and
high reliability, optimal durability and extremely long lifespan also with
low viscosity and variable quality of fuels [13]

Fuel consumption and exhaust gas emissions can be reduced by approximately 20% with better exhaust gas recirculation and by pre-heating the engine before the cold start. Further measures are:

  • Reduction of mechanical and thermal losses in the complete chain of air and fuel injection and in the exhaust gas after treatment system;
  • Use of a two-step load of the turbocharger to improve the stationary performance; and
  • Application of an electric driven exhaust gas turbocharger with less inertia [7].

11.2 Engine Operation

Engine operation mainly depends on the principle of operation, the size and the number of revolutions, often called the speed of the engine. There are slow, medium, and high speed diesel engines.

Fig. 11.2 Impact of changing fuel consumption on NOx emissions at constant rpm

11.2.1 Slow Speed Two-Stroke Marine Diesel Engines

Slow speed, high capacity marine diesel engines are the largest engines in the world which operate with a crosshead principle at a maximum of 300 rpm. Most large two-stroke, slow speed diesel engines operate below 120 rpm, even between 60 and 70 rpm. Two-stroke marine diesel engines have the best SFC among internal combustion engines. Their construction and operational characteristics are presented in Table 11.1 [8].

Slow speed marine diesel engines usually work with gate, valve, and port control as well as with a combination of them. In the largest engines only the valve and the port control are used.

NOx emissions are directly related to the combustion temperature. Decreasing the amount offuel injected into the combustion chamber usually requires more intensive mixing which increases the temperature in the burning zone and lead to locally higher NOx emissions at a constant number of revolutions (see Fig. 11.2).

11.2.2 Medium Speed Four-Stroke Marine Diesel Engines

Medium speed marine diesel engines are widely used as main and auxiliary engines. They operate on diesel fuel or heavy fuel oil by direct injection in the same manner as low speed engines. There are natural gas fueled versions, which operate on the Otto cycle and also dual fuel versions (Table 11.2) [14].

11.2.3 High Speed Four-Stroke Marine Diesel Engines

High speed marine diesel engines are usually used to provide high specific power, low weight, and small volume. They are special engines and have a maximum

Engine
parameters		 Physical properties
Operation
parameters		 The number of revolutions is between 300 and 900 rpm. The average piston
speed ranges from 8 to 9 m s-1 (from
26.2 to 29.5 ft s-1
). The cylinder
diameter is usually between 200 mm and 640 mm (7.9 and 25.2 in)
Performance The power range is from 100 to 2,150 kW (from 134 to 2,883 HP) per
cylinder
Pressure range The average pressure ranges from 200 9 105 Pa
(4.18 9 105 lbf
ft-2 or
2.901 psi) to 290 9 105 Pa
(6.10 9 105 lbf
ft-2 or
4.210 psi)

Table 11.2 Characteristics of medium speed four-stroke marine diesel engines

Table 11.3 Characteristics of high speed four-stroke marine diesel engines

Engine
parameters		 Physical properties
Operation
parameters		 The number of revolutions is over 900 rpm and the average piston speed is
between 9 and 11 m s-1 (29.5
and 36.7 ft s-1
). The cylinder piston stroke
volume reaches from 0.266 to 0.55 dm3 (from
9.3 9 10-3 to
19.4 9 10-3 ft3
). There are three, four, six, and eight cylinder versions
designed ''in-line'' and in a ''V'' shape
Future
development		 The most important possibilities are increasing the fuel injection pressure,
using variable preinjection time, applying adjustable swirl, and mass of
intake air and introducing adjustable swirl and angle of injected fuel into
the combustion chamber and regulating the ignition point depending on
the exhaust gas quality

operating engine speed between 900 and 2,300 rpm. Similar to the medium speed engine, the ignition pressure is approximately 200 9 105 Pa, i.e., 4.18 9 105 lbf ft-2 or 2,901 psi [15].

There is no sharp differentiation between medium and high speed marine diesel engine (see Table 11.3).

Medium speed four-stroke marine engines are particularly advantageous at lower speeds and lower partial loads. High speed four-stroke engines are used on sport and lifeboats, and on specific smaller ships.

Gas turbines are used on ferries and navy ships, and provide higher speeds and power ranges. They have the highest SFC under marine engines [16].

11.3 Main Operation Characteristics of Marine Diesel Engines

11.3.1 Charging Marine Diesel Engines

Charging any diesel engine with air increases its performance without increasing its speed by more than 50%. The efficiency of a turbocharger directly influences

Environment
conditions		 Operation measures
Ambient air
temperature		 Higher ambient air temperatures decrease the mass of the charging air
and the Lambda number of the combustion. Disadvantageous results
are the higher thermal load of combustion relevant parts, the higher
temperatures of the exhaust gas and the after treatment system and the
deterioration of the SFC. In principle, two-stroke and the four-stroke
engines behave similarly [19]
Charging air
temperature		 Increasing the charging air temperature reduces the requirements of the
exhaust gas after treatment system, because the quality of the
combustion improves and the concentration of unburned substances
decreases [20]
Exhaust gas counter
pressure		 Highly turbocharged marine diesel engines are very sensitive to changes
in the exhaust gas counter pressure downstream to the turbines.
Particularly two-stroke engines consume more fuel with high counter
pressure. Manufacturers usually do not permit exhaust gas counter
pressures more than 20 to 30 mbar, i.e. from 2,000 to 3,000 Pa (from
41.8 to 62.7 lbf ft-2 or
from 0.29 to 0.44 psi) [21]

Table 11.4 Influences of changing environment conditions on operation

the fuel consumption and exhaust gas emissions of the engine. Improving the turbocharger's efficiency from 60–70% decreases fuel consumption up to 2% [17].

Two-stroke engines must operate with a constant pressure in all cylinders and the charging air has to be equally distributed to all cylinders. Differences in the operation significantly influence the flow resistance. The result could be a lengthways flush with small air throughput in the cylinders. Precisely, regulating charging air supports the changing exhaust gases in the cylinders. The charging process can be further optimized by using additional compressors, e.g., electric boosters [18].

11.3.2 Operation in Changing Environment Conditions

A ship can gain or lose efficiency as the weather changes. The most important factors influencing fuel consumption and emissions are:

  • Ambient air temperature;
  • Charging air temperature; and
  • Exhaust gas back pressure (see Table 11.4).

Figure 11.3 shows the reaction of the engine to increased exhaust gas counter pressure.

Fig. 11.3 Impact of exhaust gas counter pressure on engine service data

11.3.3 Impact of Bad Weather on Engine Operation

Marine diesel engines need reserve power to compensate for increases in resistance of the ship's hull and decreased efficiency of the engine caused by wear and contamination. Minimum efficiency reserves must be 10–15%.

The engine might only keep 75–80% of its theoretical efficiency measured at the dockyard under test drive conditions. The reserve efficiency of 20–25% can cover the resistance increases and the efficiency losses without reducing the ship's speed at sea or at inland water ways.

In bad weather, speed has to be decreased depending on the power of the waves and wind. The captain has to alter course according to the direction of the waves and the wind to save fuel and maintain the ship at slower speeds. Bad weather increases the temperature and the counter pressure in the exhaust gas in all relevant elements back to the outlet valves. Sailing in bad weather for a long time can increase the risks of overheating the engine and of high-temperature corrosion in the exhaust gas after treatment system [22].

11.3.4 Cooling Circuit

The heat produced by burning in the combustion chamber must be conducted outside by a cooling medium, e.g., by air or water. Main ship engines usually use water cooling. The cooling water may have a maximum temperature of 80–90C (176–194F). Auxiliary engines often use air cooling. Tears in hot material sections which can arise from high temperature differences between heated and cooled elements can be observed by micro temperature sensors. Dangerous situations have to be always avoided.

Ship engines have two independent cooling water units:

  • Internal circulation unit which uses fresh water; and
  • External circulation unit which uses sea water [23].

Contamination of the engine parts by sea water cooling must be prevented to avoid dangerous corrosion. This technology is disappearing on ships and is being more and more replaced by block cooling systems.

11.4 Operation Monitoring in Marine Diesel Engines

In current technology, cylinder pressure, exhaust gas temperature, concentration of exhaust gas substances and several operation parameters of the main and the auxiliary engines are monitored (see Table 11.5).

Modern main and auxiliary engines of a ship mean a highly complex, electronically monitored and regulated system. In the future, state-of-the-art technology for pressure and temperature measurement can be completed with appropriate combustion sensors to record the concentration of exhaust gas substances and discover disturbances and deviations in engine, and exhaust gas after treatment system.

11.5 Development Tendencies

Although light weight materials are gaining importance in the construction of all means of transportation, many different and non-replaceable conventional materials such as steel and aluminum are still used in the production of marine diesel engines.

11.5.1 Conventional and New Materials

The development of engines with rising power increases the stresses on the valves. The temperature of the inlet valves is 500–550C (932 – 1,022F) because of the cooling effect of the fuel and air mixture. Outlet valves may reach operating temperatures of about 850C (1,562F). For this task, Hardened Alloy Ferritic-Pearlitic (AFP) such as martensitic-carbidic and austenitic-carbidic steels are being developed with higher strength [33].

The advantages of aluminum cast products are its light weight and precise tolerances. Aluminum alloys can be used for mechanical parts with small internal diameters, e.g., for cylinder elements with small oil channels or for pistons with small holes. The compressor wheels of the Exhaust Turbocharger (ETC.) can be made also of aluminum alloys. Currently, cylinder heads are made of aluminum and magnesium alloys instead of traditional gray cast iron. In the near future, aluminum alloys will be used to strengthen crankcases [34].

Ceramics made of non-metallic, inorganic materials based on nitrides, carbides and metal oxides are widely used for weight reduction, friction and wear of highly

Table 11.5 Operation monitoring of marine diesel engines

Operation
monitoring		 Operation measures
Cylinder pressure Cylinder pressure is used to control the efficiency of the cylinders.
Changing cylinder pressure can be analyzed with sensors. The sources
of efficiency losses are usually leaks in pistons, insulation rings, valves,
etc. Regulating the injection pressure maintains the life time of these
elements and saves a high quality of the injection and combustion
process [24]
Exhaust gas
temperature		 Currently, exhaust gas temperatures can be measured with micro sensors,
similarly to cylinder pressures. In the normal case, if the injection
pumps are adjusted to the same capacity and to the same performance,
the same or very similar exhaust gas temperatures exist in all cylinders
Sources of differences must be discovered [25]
Combustion process For short on-board analyzes, unburned substances can be measured with a
solid electro chemical cell, CO2
with a micro FTIR analyzer and NO
with a modified Lambda sensor. However, electro chemical cells
cannot differentiate between HC and CO, on-board FTIR analyzers are
very sensitive against particles and Lambda sensors have a cross
sensitivity to NH3.
Ammonia can be produced in the exhaust gas after
treatment system if SCR technology is applied [26]
Surge of compressor Under special operating conditions the turbocharger0
s compressor goes
into surge or stalled operation. This process produces a loud noise
because it works in an instable operation range which causes an intense
back and forth flow on the compressor rotor. The surge can be avoided
with improved operating conditions., e.g., with increased number of
revolutions of the engine, with increased temperatures in the air
entering, with cleaning the compressor, the turbine and the naturally
aspirating air filter, and with blowing off the intake air channel and the
exhaust gas channel [27].
Injection system Piezo-electrically actuated injection systems present the stand-of-the-art.
Most reasons for deviations are defects in the injection valves, in the
injection pumps and in the connected pipes. In most cases, the injection
valves are carbonized, the pre-heating temperature of the fuel is too
low or the fuel is contaminated by water. Measurement can be done
with nozzle needle and valve lift sensors, pressure, temperature and
actuator force analysis, dynamic pump drive, torque and power, and
fuel consumption consideration [28]
Inlet and outlet
valves		 Inlet and outlet valves regulate the gas recirculation. They are constructed
with overlapping. Most disturbances are related to leaky and dirty inlet
and outlet valves [29, 30]
Piston ring Statistics shows that the main reasons for repairs and changes of piston
rings are leaks [31].
Turbocharger0
s
compressor		 The nozzle ring is one of the weakest points of the turbocharger's
compressor. If the compressor's nozzle ring is worn, the cooler of the
charge-air does not operate efficiently [32]

loaded parts such as propellers. However, the costs of ceramics parts are still high. Moreover, they cannot fulfill a lot of mechanical and chemical requirements in the construction yet [35].

Fig. 11.4 Combination of the diesel-electric engine and propulsion elements

In last decades, new unconventional materials have been being developed, e.g., fine grain carbon and titanium alloys for pistons as a substitute for high-temperature steel alloys. However, the cost of alloys is high on average. Expensive alloyed parts should be partly replaced by steel with a boron or nitrogen bonus and spherical cast materials.

Synthetic materials are replacing aluminum in many parts such as in the air intake lines. The advantages of synthetic materials are their low weight and the almost unlimited possibilities for form and design. In recent years plastics have become cost competitive with alloys [36].

For economic reasons, ship construction is decreasing the mass of equipment on-board. In modern engine design, steel is being replaced by aluminum, magnesium, and synthetic materials. Apart from mass advantages, light weight materials must show a positive climate balance and high recycling rate.

11.5.2 Use of Diesel-Electric Systems

A diesel-electric transmission system includes a diesel engine connected to an electrical generator creating electricity that powers ship's electric traction engine. The first diesel-electric system was launched in 1903. One advantage of diesel electric systems is the optimal promotion of space saving. Another advantage is the possibility of using smaller subsystems instead of one large main engine, according to the specific tasks and possibilities of the ship's construction (see Fig. 11.4) [37].

The diesel electric propulsion makes the ship far more manageable. Some modern ships, including chruis ships and icebreakers, use electric motors in pods to allow for 360 rotation. Gas turbines provides in combination with electric motors a high speed and a low torque output of a turbine to drive a low speed propeller, without reduction gearing [38].

Fig. 11.5 Dissipation of energy in a slow speed marine diesel enginediesel engine

Fig. 11.6 Improvements of future injection technology

11.5.3 Improving Operation

On average, a slow speed two-stroke marine diesel engine converts more than 50% of the chemical and thermal energy to mechanical work. With the slow speed of the piston, the combustion process is more complete than in fast speed four-stroke engines. Theoretically more than 60% thermal efficiency would be possible, but a higher heat recuperation rate is not yet possible. The efficiency depends on friction losses and recuperation of exhaust gases (see Fig. 11.5) [39].

Further improving common rail injection efficiency for large two-stroke engines is one of the most important technological tasks. In common rail systems, the pressure in the fuel rail is up to 1,000 9 105 Pa (20.89 9 105 lbf ft-2 or 14,504 psi) and the valve pressure is up to 200 9 105 Pa (4.18 9 105 lbf ft-2 or 2,901 psi) [40].

Fig. 11.7 Development and prediction of important engine parameters

Higher efficiency of the injection process is the key element to further improvements (see Fig. 11.6) [41].

The slow speed two-stroke marine diesel engine technology will consolidate its leading position with higher thermal effectiveness, better resistance to wearing, longer durability, and more optimal regulation feasibility (see Fig. 11.7) [42].

The expected possible development scenarios depend on economic growth, availability of crude oil, and regulations in environmental and climate protection. Higher intelligence with self-diagnosis system can optimize the development process, save fuel, and decrease exhaust gas emissions.

11.6 Summary and Recommendations: Development of Marine Engine Technology

Most large merchant ships use two-stroke marine diesel engines. Although the number of them is much lower than the number of four-stroke marine diesel engines, the two-stroke technology makes up approximately 2/3 of the worldwide fleet performance. Smaller boats and ferries use spark ignition engines with gasoline as fuel and very fast special ships, such as war ships, use gas turbines.

Marine diesel engines apply the best self ignition technology with a high quality of mixture formation in the combustion chamber. The heat of the burning process can be used in heat exchangers of the exhaust gas section. In the last decades, the pressure in the cylinders has increased and has led to higher performance efficiency, lower SFC and decreased exhaust gas emissions.

Fast running four-stroke engines can be easily down-sized and combined with an exhaust gas after treatment system. In opposite to internal combustion engines, gas turbines are expensive and are used in high-speed ships, such as ferries. They were formerly exclusively applied in navy ships.

The progress in marine diesel engine technology over the last ten years can be summarized as follows:

  • • Performance has been increased by 42%;
  • Exhaust gas emissions have been reduced by more than 50%;
  • Fuel consumption has been lowered by 15%;
  • Smooth running has approached the standard of spark ignition engine technology; and
  • Maintenance has been reduced by about 50%.

The introduction of Self Diagnosis technology will contribute to improving fuel injection, increasing the maximum injection pressure, optimizing spraying injection process, and controlling nozzle operation.

There are four further ways to be used for near zero emission combustion:

  • Mixing the fuel and air homogeneously in the intake outside the combustion chamber;
  • Igniting fuel and air mixture with optimal compression;
  • Avoiding soot formation by effective regulation of a lean combustion; and
  • Burning fuel without flame in a porous inert medium, e.g., in a ceramic combustion chamber.

Porous ceramic burners have an exactly defined structure of holes. Engines with porous combustion chambers are still in the development stage. Particularly, monitoring and regulating have to be developed to prevent backfires and special flashbacks.

References

Chapter 12 Type Approval and Type Certification

Legislation prescribes strict procedures for the approval and the certification of vehicles, airplanes, and ships worldwide, but the requirements are different in individual countries.

12.1 Tests of Vehicles

Vehicles are checked during the production phase in the ''Compliance of production'' which tests the gas and particle emissions of new motor vehicles. This examination decides whether production may be continued or not. The statistical rule for the sampling is very different in Europe, in the USA and in California [1].

Random Field Monitoring (FM) of used motor vehicles must prove whether the exhaust gas limits are maintained after approximately 80,000 km (49,720 mi) and 160,000 km (99,441 mi). This examination decides whether the producers will get a certificate verifying the fulfillment of the regulations over the defined runtime. Otherwise the manufacturer must recall all motor vehicles of that series to get them modified.

Figure 12.1 summarizes the main methods of quality control of vehicles.

Type Approval (TA) is prescribed for manufacturers to qualify the first type of vehicles. This examination decides whether a new type of vehicle or an existing vehicle with substantially changed parts, may be produced.

In the future, Self Diagnosis can complete the methods of quality control. It can contribute to the improvement of mobile Field Monitoring.

Fig. 12.1 Main methods of quality control

12.1.1 International and National Legislation

There are many different regulations regarding exhaust gas legislation (see Fig. 12.2) [2].

Nowadays, the decreased emission limits increasingly determine the general equipment of vehicles, the fuel consumption of the engines, and the quality and the quantity of the exhaust gas after treatment systems. The worldwide limitation of exhaust gas emissions has resulted in an average decrease in the output of pollutants in the last decades. In new fleets, unburned hydrocarbons have been decreased by up to 97–98%, CO, NO, and NO2 have been reduced by up to 95–96%, and particles have been lowered by up to 90–91%.

The legislation concerning the examination of exhaust gas quality is very similar in all countries. Classification procedures are divided into processes for passenger cars, light, medium, and heavy-duty vehicles.

12.1.2 Cars, Light and Medium Heavy Duty Trucks

The examination is a highly complex and detailed procedure, which can only be done in specific certified institutions.

12.1.2.1 Procedures in the EU

In the Type approval procedure, the motor vehicle is put on a roller test stand which simulates the traction resistance on the road. The driver sees the driving cycle with accelerating, delaying, braking and stopping. Exhaust gas samples are collected in Teflon bags. Constant Volume Sampling (CVS) technology is used to achieve a constant flow rate of the diluted exhaust gas and to avoid condensation of water vapor in the sample [3].

12.1 Tests of Vehicles 175

Fig. 12.2 Test procedure in guidelines for the measurement of emissions for passenger cars

During the determination of pollutants, the exhaust gas is diluted with air. Volume flow is calculated from the air and the exhaust gas by a dilution ratio of approximately 1:8. A part of the exhaust gas is collected in three bags, from the three sections of the US driving cycle. The European test procedure combines the three samples into one bag. In addition, a part of the ambient or outside air is filled into three bags or into one bag to provide a comparison to the basic pollution level.

The concentrations of the exhaust gas sample and of the ambient air components are measured with certified analyzers. The concentrations in the ambient air must be subtracted from the exhaust gas sample. The multiplication of the concentration with the flow rate and the integration over the whole driving route yields the weight of emissions per distance in g km-1 or g mi-1 for passenger cars and emissions per performed work in g (kW h)-1 or g (bhp h)-1 for heavy commercial vehicles.

In the EU, cars and light duty vehicles are examined at roller test benches. The emissions of complete HDVs are estimated only for experiments at a specific roller test bench if it is required during the development. The engines of heavy-duty vehicles are usually examined at the engine dynamometer test bench. In both cases, at the roller and the dynamometer engine test bench, the driving cycle is regulated and steered by a computer program. The operation can be processed by test drivers who drive the car in accordance with the commands on the computer display. These displays give the speed and the gear including braking and accelerating. The other way is the use of automats which move pedals and levers in the car with bowden cables or steering bars.

12.1.2.2 Procedures in the USA

In the USA, the Federal Test Procedure (FTP) 75 is similar to the NEDC in Europe [4]. However, in contrast to the European procedure, in the US FTP 75 test separate driving cycles are prescribed for the high-speed portion (UDDS), for aggressive driving characteristics (US06) [5], for driving with operating auxiliary

Fig. 12.3 US driving cycles for passenger cars

devices, e.g., lights and air conditioning system (SC03) [6] and for the Highway Driving Cycle (HDC) (see Fig. 12.3) [7].

The Start Control Cycle SC 03 is driven after the appropriate preconditioning and subsequent 10 min holding time with the air conditioning switched on at an ambient temperature of 35C (95F).

In the US 06 cycle, emissions are measured at high average speeds. It is used as a ''hot-start test'' at the normal test temperature of 20–30C (68–86F). The full test consists of preconditioning the engine to a hot stabilized condition, as specified in §86.132-00.

In the USA, the balance between several methods is permitted. The substitution of different methods is possible if they contribute to the improvement of air quality and emissions do not exceed the limits.

12.1 Tests of Vehicles 177

Fig. 12.4 Japanese Driving Cycle JC 08 for passenger cars Luca Gray (08/12/11)

Emissions of heavy-duty vehicles are tested in the USA at a roller test bench with specific dynamometer transient driving cycles for HDVs. The methods in the USA are similar to the European Cycles in principle, but have a different specific speed profile and specify different gears [8].

12.1.2.3 Procedures in Japan

In Japan, there are old driving cycles such as the Japanese 11 and Japanese 10 ? 15 modes [9], and new cycles such as the Japanese Cycle JC 08 for passenger cars and Japanese Cycle JE 05 for heavy commercial vehicles [10, 11].

The length of 11 mode cold cycle is 4.084 km and the time is 480 s. It involves a maximum speed of 60 km h-1 , i.e., 37.3 mph and an average speed of 30.6 km h-1 , i.e., 18.6 mph.

The 10 ? 15 mode is a hot cycle. The driving time is 892 s; the distance is 6.34 km, i.e., 3.94 mi, the average speed is 25.61 km h-1 , i.e., 15.9 mph; and the maximum speed is 70 km h-1 , i.e., 43.5 mph. Emissions are measured in the last four segments over 4.16 km, i.e., 2.6 mi in the time interval of 600 s.

The Driving Cycle JC 08 is measured over a distance of 8.2 km, i.e., 5.1 mi, and a time of 1,205 s at an average speed of 24.4 km h-1 , i.e., 15.2 mph with a maximum speed of 80 km h-1 , i.e., 49.7 mph (see Fig. 12.4).

12.1.3 Heavy Duty Vehicles

The control cycles are different in the EU, the USA, and Japan, similarly to the passenger car control methods. However, there are harmonized test cycles which are based on world-wide pattern of real heavy commercial vehicle use. Two representative cycles, a transient test cycle (WHTC) with both cold and hot start requirements and a hot start steady-state test cycle (WHSC) belong to the cycle. The test time of WHTC is 1,800 s with several monitoring segments [12].

Fig. 12.5 Structure of international and national aviation organizations

12.2 Tests of Airplanes

The International Operation Safety Audit (IOSA) of the IATA for the airlines and the ICAO for the government belong to the international organizations [13]. Membership obligates each member state to apply and to keep the ICAO standards and recommendations in their national legislation concerning aviation. In most countries, the Ministry for Transportation is the highest national authority in aviation [14].

Figure 12.5 shows the structure of international and national organizations. The criteria for airplane certification are:

  • The prototype must be approved;
  • The airworthiness must be checked;
  • The owner must be insured;
  • The airplane must be registered in the list of the official national aircraft; and
  • The maximum permissible noise, gas and particle emissions must be lower than the limit [15].

IATA vision 2050 represents a positive trend for the air transport industry by 32 million jobs, €2.45 trillion, i.e., US \$3.5 trillion in economic activity and a growth up to 16 billion of passengers and 400 million tons of freight yearly [16].

12.2.1 Emission Requirements

The main procedure is the Type Sample Test examination prescribed in the airworthiness requirements [17]. The aviation authority is responsible for carrying it out, but the test can be delegated to development companies. It is usually done for the military by the office for military technology and procurement [18].

2) Type Certificate for Holders and A/C Manufacturers 1) National Authority

Table 12.1 EASA

Table 12.1
EASA
requirements for aviation		 Requirement Content
CS-22 Sailplanes and powered sailplanes
CS-23 Normal, utility, aerobatic, and commuter
airplanes
CS-25 Large airplanes
CS-27 Small rotorcraft
CS-29 Large rotorcraft
CS-31 Hot air balloons
CS-34 Aircraft engine emissions and fuel venting
CS-36 Aircraft noise
CS-APU Auxiliary power units
CS-AWO All weather operations
CS-E Engines
CS-ETSO European technical standard orders
CS-Definitions Definitions and abbreviations
CS-P Propellers
CS-VLA Very light airplanes
CS-VLR Very light rotorcraft
AMC-20 General acceptable means of compliance for
airworthiness of products, parts and
appliances

The regulations called Joint Aviation Requirements (JAR) are published by the Joint Aviation Authorities (JAA) on behalf of the member states [19]. The JAA was founded by the European Civil Aviation Conference (ECAC) which is the European organization of the ICAO. The members are the ministers for transportation of the European countries and representatives from the European Aviation Safety Agency (EASA) which is the airworthiness authority for aviation in the EU [20].

The JAA have adopted a set of harmonized rules for commercial air transportation, called Joint Aviation Requirements for Commercial Air Transportation (Airplanes) (JAR-OPS 1). These regulations provide for common safety standards of the designers, the manufacturers, the operation and the maintenance of the aircraft, as well as aviation personnel and organizations. In detail, the regulations contain requirements for the flying characteristics, the construction, the engine installation, the type and the operation limits of equipment. The civilian construction specifications have to refer to a series of requirements according to the JAA [21].

The JAA is an organization operated by volunteer European Civil Aviation Authority (CAA). EASA has taken over most of the JAA regulations, thereby creating the EASA requirements which are presented in Table 12.1. [22].

Fig. 12.6 Sampling at the test bench

12.2.2 Sampling, Sample Transfer, Instrumentation and Measurement Technology

The instrumentation and measurement technology requirements of jet engines are regulated in Appendix E of JAR-34, Section 1 of ICAO (Appendix 5 of Annex 16, Volume II) [23].

The test must be done at the required thrust setting on a properly equipped test bench. The engine must be stabilized at each setting and the probe must be made of stainless steel. If a mixing probe is used, all sampling orifices must be of equal diameter. The proposed design and position is shown in Fig. 12.6.

The sample must be transferred from the probe to the analyzers via a tube with an internal diameter of 4.0–8.5 mm (0.157–0.334 in), taking the shortest practical route and having a flow rate of less than 10 s. The tube must be heated to 160C ± 5C (320F ± 41F).

The branch tube must be maintained at a temperature of 65C ± 15C (149F ± 59F). When sampling to measure unburned hydrocarbons, CO, CO2, NO, and NO2, the tube must be made of stainless steel or carbon-loaded grounded Teflon.

Basically, the analyzers for testing the engines of vehicles, airplanes, and ships are the same. The total amount of hydrocarbons can be analyzed with a heated FID, CO, and CO2 concentrations can be determined with a non-dispersible infra-red (IR) analyzer and NOx concentrations can be measured by CLD (see Fig. 12.7).

12.2.3 JAR-E and CS-E for the Certification of Engines

JAR-E is based on European Civil Aviation Requirements (ECAR) Section C and is termed JAR for engines. It contains the airworthiness requirements of all aircraft engines [24, 25]. The relevant EASA, Subpart A-General regulations are contained in Table 12.2 [26].

Fig. 12.7 Exhaust gas analysis system for Type certification of aircraft engines

Table 12.2 Requirements of the sub-section A of the EASA

Requirement Contents
CS-E 10 Applicability
CS-E 15 Terminology
CS-E 20 Engine configuration and interfaces
CS-E 25 Instructions for continued airworthiness
CS-E 30 Assumptions
CE-E 40 Ratings
CS-E 50 Engine control system
CS-E 60 Provision for instruments
CS-E 70 Materials and manufacturing methods
CS-E 80 Equipment
CS-E 90 Prevention of corrosion and deterioration
CS-E 100 Strength
CS-E 110 Drawings and marking of parts—assembly of parts
CS-E 120 Identification
CS-E 130 Fire protection
CS-E 140 Test—engine configuration
CS-E 150 Tests—general conduct of tests
CS-E 160 Tests—history
CS-E 170 Engine systems and component verification
CS-E 180 Propeller functioning tests
CS-E 190 Engines for aerobatic use

The relevant EASA regulations are:

  • Subpart B: Piston engines, design, and construction;
  • Subpart C: Piston engines, type substantiation;

Table 12.3 Provisions for the design and construction of Auxiliary Power Units

Requirement Contents
CS-APU 210 Safety analysis
CS-APU 220 Fire prevention
CS-APU 230 Air intake
CS-APU 240 Lubrication system
CS-APU 250 Fuel system
CS-APU 260 Exhaust system
CS-APU 270 Cooling
CS-APU 280 Over-speed safety devices
CS-APU 290 Rotor containment
CS-APU 300 Vibration
CS-APU 310 Life limitations
CS-APU 320 Bleed air contamination
CS-APU 330 Continued rotation
  • Subpart D: Turbine engines, design, and construction;
  • Subpart E: Turbine engines, type substantiation; and
  • Subpart F: Turbine engines, environmental, and operational design requirements.

Fuel venting (CS-E 1010) and engine emissions (CS-E 1020) belong to Subpart F. For Self Diagnosis, the CS-E 1020 has a decisive character. It must be demonstrated that the engine type design complies with the emission specification of CS 34.2 in effect at date of engine certification.

12.2.4 Certification of Auxiliary Power Units

The Joint Aviation Requirements for Auxiliary Power Units (JAR-APU) are based on the FAA's Technical Standard Order TSO-C77a [27]. Subpart A provides the airworthiness requirements for the issue of Joint Technical Standard Order (JTSO) authorizations for turbine powered APUs used on an aircraft [28].

The relevant EASA, Subpart B design and construction regulations for all types are contained in Table 12.3 [29].

APU 250 and 260 deal with fuel consumption and emissions. In accordance with these requirements the exhaust gas systems must be designed and constructed to prevent leakage of exhaust gases into the aircraft. The exhaust piping has to be constructed of fireproof and corrosion resistant materials.

The relevant EASA regulations of Subpart C for all APU type substantiations are shown in Table 12.4.

Subpart D contains the additional requirements (see Table 12.5).

Table 12.4 Subpart C for all

Table 12.4
Subpart C for all
APU type substantiations		 Requirement Content
CS-APU 410 Calibration tests
CS-APU 420 Endurance test
CS-APU 430 Tear down inspection
CS-APU 440 Functional test of limiting devices
CS-APU 450 Over-speed test
CS-APU 460 Over-temperature test
CS-APU 470 Containment
CS-APU 480 Electronic control system components

Table 12.5 Subpart D for all

Table 12.5
Subpart D for all
APU type substantiations		 Requirement Content
CS-APU 510 Ice protection
CS-APU 520 Foreign objects
CS-APU 530 Automatic shutdown
CS-APU 540 Ignition system

12.3 Tests of Ships

International conventions for shipping are made by maritime umbrella organizations like the IMO, as well as the International Labor Organization (ILO). Both are executive organs of the United Nations (UN) [30].

IMO is responsible for SOLAS that is concerned with all aspects of seagoing vessels' safety [31]. This includes the construction of ships regarding their stability after damage, the fire protection of the structure and the operation, the safety devices, the control of the ship's machinery in emergencies, the equipment for personnel and the installed safety devices for distress communication, as well as the transportation of hazardous materials. Furthermore SOLAS 95 requires shipping companies to comply with the International Safety Management (ISM) code [32].

Within the IMO, the Maritime Safety Committee (MSC) is responsible for the examination of proposals and working out appropriate supplements to SOLAS on the basis of the proposals [33].

12.3.1 Classification and Judgment

Classification and judgment, the organization of ships into classes, the regular supervision of their maintenance, the standards for design, construction or construction specifications, and marine technology research are done by the International Association of Classification Societies (IACS) [34]. The oldest classification society, Lloyd's Register Group for shipping, was founded in London in 1760 with

the main goal of enhancing the safety of life and property for the benefit of the public and ultimately, the environment [35].

Nowadays, there are ten internationally recognized classification societies which are organized under an umbrella organization in the IACS. There are further approximately 30 other classification societies which do not correspond to the international quality standards of the IACS.

Statutory inspections manage security on-board, supervise safety regulations for labor conditions, and for environmental protection that are made by flag states. Class-conforming ships receive corresponding certificates from the classification society [36]. They contribute to maritime safety and regulation through technical support, compliance verification, and research and development. More than 90% of the world's cargo carrying tonnage is covered by the classification design, construction compliance and life-cycle assessment. Rules and standards set by the member societies of IACS.

12.3.2 International Environmental Regulations

Regulations for the Prevention of Air Pollution from ships were adopted in the 1997 Protocol to MARPOL 73/78 and are included in Annex VI of the Convention [37]. They came into force in 2005 after ratification by 15 member states of the IMO, which represent more than 50% of the world tonnage. Regulations 13 and 14 of the Annex VI set limits for NOx from diesel engines and for SOx emissions from ships [38].

Similar to aviation technology, the rules of the IMO are valid internationally in contrast to road transportation whose rules are only valid within national or regional frames. The IMO regulations are moderately competition-neutral.

Monitoring takes place via national classification societies, professional environmental associations and government port controls. Classification societies have also created new classes like the Environmental Passport [39], the awards for Environmental Protection [40], Clean Ships and Clean Design in recent years [41].

In 2010, the Marine Environment Protection Committee (MEPC) [42] of MARPOL introduced two drafts, the Energy Efficiency Design Index (EEDI) [43] and the Ship Efficiency Management Plan (SEMP) [44] for decreasing Green House Gas (GHG) emissions for the UN Framework Convention on Climate Change (UNFCCC) [45].

12.3.3 Sulphur Concentration

A special problem arises from the sulphur content of heavy marine fuels on ships (see Table 12.6) [46].

Type of fuel Sulfur content in the past
mg kg-1 (ppm)		 Decreased sulfur content
mg kg-1 (ppm)
Gasoline 10 0.01 from 2003
Super plus 10 0.01 from 2003
Diesel oil 19 0.01 from 2003
Light heating oil 2,000 2.00 from 2008
Kerosene 300 0.30 according to IP 336
Heavy oil (land) 10,000 (1.0%) 10.00
Heavy oil (sea) 45,000 (4.5%)a 45.00

Table 12.6 Sulfur limits for liquid fuels in Germany

The sulfur content of heavy fuel oils in maritime shipping is regulated according to the MARPOL 73/78 Convention, Annex VI, revised in 2008, which entered into force on 1 July 2010. In special cases, Sulphur Emission Control Areas (SECA), such as the Baltic Sea, the North Sea, and the English Channel, the sulfur content has been limited since 2006. Consequently, this requirement has led to the use of two different fuels on-board. Certified exhaust gas after treatment devices can be alternatively used, which further effectively limit the SOx content in the exhaust gas. The sulfur content of the fuel and the time to switch to low sulfur fuel must be documented upon entry into a SECA area [47].

However, before ships generally can use low sulfur fuel, the following requirements must be fulfilled:

  • The supply must be standardized worldwide;
  • The quality must be sufficient and constant; and
  • The color must be corresponding for separation from other fuels [48].

Environment and climate protection and the increasing cost of fuels intensively influence the introduction of new fuel types. In the future, more parallel supply systems must guarantee save supply with different qualities of fuels. However, it is expected that the complementary measures for the storage and the use of different quality fuels will lead to higher costs.

The problem of the compatibility of fuels affects both the main and the auxiliary engines because ships use fuels from the same tank not only for the propulsion but for heating and cooling and other purposes.

12.3.4 Nitrogen Oxide Concentration

The MARPOL 73/78 Convention, Annex VI, Regulation 13 sets the limits for nitrogen oxide emissions of international seagoing vessels [49].

Strengthened emission standards for new ships were adopted by the IMO in 2008, NO x emissions from international shipping in European sea areas are

a 1.5% in Baltic and North Sea and in the English channel

Fig. 12.8 NOx emission limits in MARPOL 73/78, Annex VI

projected to increase by nearly 40% between 2000 and 2020. The reason is that by 2020, the emissions from shipping around Europe are expected to equal or even surpass the total from all land-based sources in the 27 EU member states combined. In addition to the NO x requirements for new ships from 2011, the IMO decided that in ECAs, ships built after 01 January 2016 will have to reduce emissions of NO x by about 80% from the current limit values.

Figure 12.8 shows the course of NOx limits depending on the number of revolutions [50].

Besides international legislation, national regulations also limit exhaust gas emissions, e.g., in Sweden, in Norway and in the USA. The authority in Alaska limits the visible emissions of seagoing vessels by the Alaska Marine Vessel Visible Emission Standard (18 AAC 50.070). The exhaust opacity at the end of the exhaust pipes is limited to 20%. Short excesses are allowed during maneuvering [51].

Europe Directive 97/68/EC, amended by 2004/26/EC, sets limits on the emissions of diesel engines on inland navigation vessels [52, 53]. The limits correspond to step two (Tier II) of the US EPA ship guidelines [54].

12.4 Summary and Recommendations: International Type Approval and Type Certification

There is a large variety of laws and regulations concerned with reducing fuel consumption and emissions. Despite this variability, the procedures for quality control, production and operation are very similar for vehicles, airplanes and ships.

12.4.1 Vehicle Type Approval

Type Approval is the most important procedure for the permission of mass production of vehicles.

The complete TA procedure is regulated by the Type approval (TA), the Conformity of the Production (CP), the Field Monitoring (FM) and the Exhaust Gas Batch Testing (ET). After purchase, motor vehicles are monitored through exhaust gas checks organized by individual national authorities, examples of which are the ''Ministry of Transport in England'' (MOT), the ''Inspection and Maintenance'' in the USA (IM), the ''Technischer Überwachungsverein in Germany'' (TÜV), the ''National Car Test in Ireland'' (NCT) and the ''Green Card'' (GC) service in Hungary.

There are three artificial driving cycles for passenger cars:

  • The European NEDC;
  • The US American FTP 75; and
  • The Japanese JC 08.

Individual countries use one of these three procedures based on their political and technological connections. In the future, the unification of these procedures for passenger cars, similar to heavy duty vehicles could support cost effective production of vehicles, make it easier to sell them on the world market and reduce the purchase price. There are good examples such the World Harmonized Stationary Cycle (WHSC) for a hot start steady state cycle and the World Harmonized Transient Cycle (WHTC) with both cold and hot start requirements for heavy commercial vehicles.

12.4.2 Airplane Type Certification

Airworthiness certification and verification of airplanes is checked by routine test runs carried out by the manufacturer. For an airplane already in production, the responsible national authority approves the individual airworthiness certificates.

The exhaust gas composition of unburned substances such as HC, CO and NO, NO2, particles, and noise of jet engines and APUs have to be examined according to JAR-E Technical Standing Order and EASA regulations within the Type certification.

JAR-E is based on ECAR Section C and is termed JAR for engines. It contains the airworthiness requirement of all aircraft engines. Further relevant EASA regulations are subpart B for piston engines, design and construction, subpart C for piston engine, type substantiation, and subpart D for turbine engines.

12.4.3 Ship Certification

The ship certification depends on the regulations, ratified by the IMO. Basic safety requirements are specified in the EU in EEC and EC guidelines, which are to be partially taken over by national governments. Leading the proceedings in Europe are the environmental requirements for the Rhine, contained in the Central Commission for Navigation on the Rhine (CCNR). Further important guidelines for ship certification are:

  • 96/98/EC concerning marine equipment amended by 2002/75/EC [55][56];
  • 98/18/EC concerning safety regulations and standards for passenger ships amended by 2002/25/EC and 2003/24/EC [57][58][59];
  • 1999/5/EC concerning radio installation and telecommunication terminal equipment according to international requirements of the Committee International Special des Perturbations Radioelectriques or International Special Committee on Radio Interference (ISPR) [60];
  • 2004/108/EC concerning electromagnetic compatibility [61]; and
  • 2006/87/EC concerning technical requirements for vessels on inland waterways amended by 2008/87/EC, 2008/126/EC and 2009/46/EC [62][63][64][65].

References

References 189

  1. Certification specifications. http://www.easa.eu.int/agency-measures/certification-specifications. php

Chapter 13 Inspection and Maintenance

The inspection of vehicles, airplanes and ships is defined by different directives; but there are common points regarding the inspection measures in all types of transportation, which:

  • Give standards for the necessary repairs;
  • Provide information on the quality of the construction and the operation; and
  • Explain the reactions of vehicles, airplanes and ships caused by certain loads.

The inspection and maintenance characteristics of ships, road vehicles, or airplanes result from the interaction of their parts, loads, and function and cannot be determined using individual parameters. Each disturbance of a system component can lead to losses in production, and in operation which can directly cause disadvantages to the manufacturer and to the transportation company. Inspection prevents losses and disturbances in operation and safety (see Fig. 13.1) [1].

Inspection and maintenance mean a system of actions that responds to loss of performance of engine and operation of road vehicle, airplane, and ship because of wear. This includes instructions and standards for preparation and operation checks, approvals and permissions, as well as evaluations and feedbacks. Like the cost of fuel, the costs for inspection and maintenance are an important part of the operating costs which can be effectively affected during the development as well as the operation phase. Inspection and maintenance intensively impact also the economy (see Table 13.1) [2].

Inspection and maintenance planning recognizes the critical links between transportation and other societal goals. The planning process is more than merely listing transportation projects. It requires developing strategies for operating, managing, and financing the area's transportation system in such a way as to advance the area's long-term goals [3].

It is estimated that corrosion costs ca. 4.8% of Gross National Product (GDP) [4]. Logistics amounts approximately 18.5% in GDP, and 80% of them are resulted from investment by private enterprises or individuals, and the rest from investment

Fig. 13.1 Schedule and execution of vehicle repair

Table 13.1 Cost factors of inspection and maintenance

Influence of operation Issues of inspection and maintenance measures
Economic Increasing costs of engine systems and complete ships
Increasing costs of inspection and maintenance
Technical Increasing automatic, monitoring and regulating processes
Increasing rapidity of innovations
Social and environmental Stricter rules for climate and environmental protection
Shortage of resources
Higher expectations of inspection and maintenance

by the public sector (national, state, or local governments). Estimated that inspection and maintenance costs are from 2 to 15% of the world's total transportation costs [5].

13.1 Inspection and Maintenance in Road Transportation

Inspection has very similar procedures in all regions of the world. Small differences in practice result from the different infrastructure of control organizations and vehicle manufacturers.

Computer supported diagnostic methods are increasingly used in the inspection and examination procedures. Current diagnostic systems contain electronic

Fig. 13.2 Control of heavy duty vehicles with ''free acceleration''

Table 13.2 Main OBD functions in a spark ignition engine

| Continuous monitoring systems | Sporadically monitoring systems | | | |-----------------------------------------|---------------------------------|--|--| | Irregular operation of engine (misfire) | Catalyst function | | | | Mixture adaptation (self adjustment) | Catalyst heating | | | | Other exhaust gas relevant components | k sensor | | | | CAN bus communication | Secondary air system | | | | | Exhaust gas refeeding | | | | | Tank ventilation system | | | | | Tank leak diagnosis | | |

equipment and an external test device, which can be adapted to the motor vehicle via an OBD interface (see Fig. 13.2) [6].

After the connection with the interface, the test equipment automatically adjusts itself to the data transfer system used by the engine control device. The standardized format is specified for the nomenclature of components and systems which are obligatory for all manufacturers.

13.1.1 OBD in Vehicles with Spark Ignition Engine

Electronic systems and computer technology open novel possibilities for electronic detection of errors in motor vehicles. Monitoring was first introduced in spark ignition engine technology. Nowadays, OBD controls the function of all exhaust gas components with a comprehensive monitoring system (see Table 13.2) [7].

Because of the multiplicity of information, the signals of individual elements are transferred via a CAN bus to the motor management system.

Fig. 13.3 OBD system in spark ignition engines

Figure. 13.3 shows the complexity of the OBD in a spark ignition direct injection engine, model DI Motronic which has an Electronic Accelerator Gas pedal (EGAS), an Engine Control Unit (ECU) and an electronically controlled exhaust gas recirculation system [8].

Combustion system Exhaust gas after treatment
Irregular operation of engine (misfire) Exhaust Gas Recirculation (EGR)
Fuel amount Particle filter
Charge pressure Control devices
CAN bus communication k sensor

Table 13.3 Main functions of OBD in self ignition engines

Misfires causing an engine to run roughly are the most serious indication of ignition problems. There are two different classes of misfires

  • Irregular operations that endanger the engine; and
  • Exhaust gas misfires that endanger the catalyst.

OBD technology permanently records the rough running of the engine from the angle speed of the crankshaft. If the rough running exceeds the limit, the number of misfires is counted [9].

The monitored systems are checked at specified intervals once per driving cycle, if the main operating conditions are within the defined range. The conditions are the operation temperature of the catalyst, the temperature of the coolant, the number of revolutions, the engine load and the status of the secondary air system. If the conditions are not in the defined range, the diagnostic function is not processed [10].

Besides thermal or mechanical deterioration of the catalyst, the normal aging process lowers its normal conversion rate. The exhaust gas after treatment system contains the mixture controlling and monitoring k sensors. The catalyst's oxygen storage capability is measured to determine its operability. The storage capacity is represented by the comparison of the mixture controlling k signal (upstream of the catalyst) with the monitoring k signal (downstream of the catalyst) [11].

The tank ventilation system is controlled by the electric function of the tank ventilation valve. In Europe, tank leak diagnosis is not required in contrast to the OBD II in the USA. The manufacturer must merely ensure the tightness of the filler cap. This can be done with the help of an electronic control system or a security tape [12].

13.1.2 OBD in Vehicles with Self Ignition Engine

The monitoring of self ignition engines originates from the technology in spark ignition engines. In Europe, the legal system of rules (98/69/EC) comprehensively prescribes the requirements of the OBD technology in vehicles with a self ignition engine (see Table 13.3) [13].

The OBD in a self ignition engine with Common Rail technology is shown in the Fig. 13.4 [14].

  • air control valve 1.
  • fuel filter 2.
  • high pressure pump with additional pump 3.
  • fuel pressure sensor 4.
  • fuel tank with fuel level indicator and electronic fuel pump 5.
  • Common Rail pressure control valve 6. 7.
  • air injector 8.
  • phase sensor 9.
  • revolution and relation indicator 10.
  • accelerator pedal 11.
  • brake indicator switch 12.
  • clutch pedal 13.
  • EGR valve with pressure regulator 14.
  • vacuum tank 15.

  • vacuum pump 16.

  • exhaust turbocharger 17.

  • intake pipe pressure and exhaust 18.

  • gas temperature sensor air flow meter 19.

  • exhaust temperature sensor 20.

  • wide range λ sensor 21.

  • oxidation catalyst 22.

  • exhaust temperature sensor NO sensor X 23. 24.

  • Ad-Blue tank 25.

  • Ad-Blue pump 26.

  • reduction catalyst 27.

  • particle filter 28.

  • difference pressure sensor 29.

  • engine control device malfunctioning indicator light (MIL) 30.

  • diagnosis interface 31. 32.

Fig. 13.4 OBD system in self ignition engines

The OBD system must monitor the exhaust gas components, the subsystems and the electric components, whose malfunction could lead to exceeding the defined limits. The standardized MIL signals the errors.

Faulty injection as well as loss of compression as a result of mechanical disturbances in the engine leads to incomplete combustion with increased emissions.

Fig. 13.5 Distribution of particle diameters

The rough running of the crankshaft is basically monitored to recognize combustion misfires, similar to the spark ignition engine technology [15].

A usual reason for increased fuel consumption is a change in the injection time caused by wearing and aging. For the exact recognition and corresponding compensation of the deterioration, a small quantity of the fuel is injected into the cylinder. A revolution sensor recognizes the resulting change in the number of revolutions which is coupled with the amount of fuel injected. The process is repeated in all cylinders at different operation points. The fuel consumption can be corrected through an adjustment of the access time of the injectors [16].

The pressure of the turbocharger can also be controlled in certain time intervals. Changes in the position of the turbine wheel and the bypass valve of the exhaust gate cause a decrease of the charging air pressure which is monitored by pressure sensors [17].

Self ignition engines with a Common Rail system do not produce big particles which can be monitored by measuring the opacity of the exhaust gases. Modern self ignition engines, with a high pressure level of injection of fuel and intake air, produce small particles (see Fig. 13.5) [18].

The emission of particles can be checked in the ''free acceleration'' process at the test bench. However, an idling self ignition engine produces fewer particles or none at all compared to real driving on the road. Therefore, the measurement of the opacity correlates only in an indirect way with the real mass and number of particles [19].

Micro particle sensors are still in development. The requirements are extremely high. On-board sensors must work under the hardest operating conditions. Components must bear dirt, wetness, blows and temperature changes during daily operation. Despite their small size, micro sensors are very complex in construction and operation. For safety reasons a redundant system, consisting of two intelligent sensors for each important function, could be necessary [20].

Main elements Involved tasks and work methods
Lubrication Lubricate nose landing gear retract actuator
Service Check APU oil level and add oil as required
Operational check Check voice recorder
Functional check Check cargo overheat temperature switch
General visual
inspection		 Inspect pneumatic nose assembly of off-wing escape slide
Detailed inspection Inspect check valve flapper and hinge pin of equipment cooling supply fan
Visual check Observation to determine items not fulfilling their intended purpose
(non-quantitative tolerances)
Special detailed
inspection		 Inspect the combustion chamber
Restore Clean cabin pressure outflow valve gates and seals
Discard Replace air-prefilters for recirculation

Table 13.4 Main elements and tasks involved in an aircraft inspection

13.2 Inspection and Maintenance in Aviation

Inspection and maintenance measures may include ensuring compliance with Airworthiness Directives (AD) or Service Bulletins (SB). Increased fuel consumption is often the initiator of an inspection and maintenance measure [21, 22].

13.2.1 Inspection of Airplanes

An airline must not operate unless it is controlled and released to service by an approved maintenance organization, i.e., JAR—145 or EASA Part—145 applies. Aircraft inspection leads to maintenance with overhaul, repair or modification of the aircraft or the aircraft's components [23]. The inspection checks all components of an aircraft or aircraft sub-assembly, but does not include:

  • Elementary work, such as removing and replacing tires, inspection plates, spark plugs, checking the cylinder compression;
  • Servicing, such as refueling and washing windows; and
  • Any work done on an aircraft or aircraft component as part of the manufacturing process, prior to the issue of the certificate of airworthiness or other certification documents (see Table 13.4) [24].

Fig. 13.6 Flow diagram for the maintenance plan

13.2.2 Maintenance of Airplanes

Requirements and aims are described within the Maintenance Program (MP) and methods are summarized in the Aircraft Maintenance Manual and in the Task Cards [25]. The work of the maintenance is recorded by the Maintenance Review Board (see Fig. 13.6) [26, 27].

The extent of the maintenance event depends on the number of flight hours, the number of landing cycles, and the time elapsed. Each event in the life of an airplane, e.g., flight, maintenance, and repairs that are evaluated and recorded have an influence on the MP [28].

Maintenance events include the routine examination of technical systems which are important for the daily operation as well as a thorough overhaul of the airframe. Depending on the aircraft type, the A Check must be done every 350–650 flying hours and the B Check approximately every 3 months. The C Check means the detailed inspection of the airplane structure and the test of the system. Depending upon the type of aircraft, the C Check is done every 12 months (see Table 13.5) [29].

Measurement of combustion processes does not belong to the typical control of engine technology yet, although changes due to wear caused by engine operation lead to higher fuel consumption and higher exhaust gas emissions.

13.2.3 Maintenance Steering Group

The Maintenance Steering Group (MSG) has its own type of maintenance philosophy and requires a change within the organization of air carriers [30].

A MSG-3 supports the operational safety net and provides a positive contribution to the fiscal bottom line of air carriers. It was released by the Air Transport

Time
Event		 Interval Time on ground Man hours
Trip check Before every flight 35 min 0.5
Service check Weekly 4 h 20
A check 250 flight hours (4 weeks) 6 h 40
B check 900 flight hours (3 months) 12 h 150
C check 3,000 flight hours (12 months) 30 h 700
IL checkb First interval 12 500 flight hours (5 years)
Following interval 6,500 flight hours (3 years)		 2 weeks 12,000
D checkc First interval 25,000 flight hours (9 years)
Following interval 12,500 flight hours (5 years)		 4 weeks 30,000

Table 13.5 Example of the inspection events of an airplanea

Association (ATA) of America in 1980. Its forerunners, MSG-1 (1968) and MSG-2 (1970), were used to encourage the industry to move away from the overhaul mindset. The basic overhaul is done to almost everything on an airplane at a fixed time interval, e.g., every 6 years. The MSG system has an engineering plan that determines the most appropriate maintenance task and interval for an aircraft's major components and structure [31].

The definitions of the most important elements are in the MSG-2 memorandum:

  • Hard-Time limit (HT) which is the maximum interval for performing maintenance tasks. The intervals usually apply to overhaul, but are also used for the total life of parts;
  • On Condition (OC) means repetitive inspections or tests to determine the condition of systems or structural parts; and
  • Condition Monitoring defines items that have neither ''Hard Time'' limits nor ''On Condition'' maintenance as their primary maintenance process. It is responsible for finding and resolving problem areas [32].

13.3 Engine Deteriorations

An aircraft's lifespan is measured in pressurization cycles. An aircraft is pressurized during flight each time therefore, its fuselage and wings are stressed. In jet engines, gas turbine compressor blades are easily affected by pollutants, water droplets, and other particles in the air. Both are made of large, plate-like parts connected with fasteners and rivets, and over time, cracks develop around the fastener holes due to metal fatigue [33].

Erosion in the compressor and the carbonization of nozzles are the main sources of wear in engines during flight (see. Fig. 13.7).

a Designed in the 1970s and 1980s

b, c The prime aim of the IL and the D check is the maintenance of the structure

Fig. 13.7 Increasing fuel consumption of jet engines depending on flight cycles

The erosive agents damage a turbine engine's performance, lead to thermal deformations, increasing splits and decreasing efficiency. A new erosion-resistant nano coating is benefitting both of these sectors in significant ways [34].

However, due to the high load of turbines' blades, deteriorations are natural processes and continuously impact fuel consumption, CO2 and pollutant emissions in the exhaust gas. New development results, electronic monitoring and Self Diagnosis of the combustion process are gaining increasing importance because of the growing complexity of engine system technology.

13.4 Commander's Responsibility

Before any departure, there is a visual check of the airplane's outer surface and parts for damage, leaks, missing parts and an inside check that the aircraft systems are functioning properly. Furthermore, crew have to study the documents on previous maintenance activities and maintenance related crew reports filed in the operator's on-board technical flight log, i.e., the Airplane Flight Log (AFL) and the Deferred Item Record (DIR) [35].

The decision to ''go''/''not go'' is aided by the manuals Minimum Equipment List (MEL) and Configuration Deviation List (CDL) concerning those missing or inoperable minor items and related actions to be followed which can be tolerated for a short period of time without compromising safety [36, 37].

13.5 Inspection and Maintenance in Ships

Maintenance means the combination of all technical and administrative measures during the whole life time of a ship. The most important measures are checking the systems, investigating errors and repairing or replacing defective modules (see Table 13.6) [38].

Items Maintenance Inspection Overhauling Improvements
Aims Delay of
degradation
of the tank
through
erosion		 Determination and
evaluation of the actual
conditions and causes of
wear, estimation of
consequences		 Recirculation
in a useable
condition		 Safety
enhancement
Activities Cleaning,
lubricating,
greasing, etc.		 Visual control or measurement
with help of analyzing
technology		 Exchange
or repair of
components		 Guarantee of
future
function

Table 13.6 Goals and details of maintenance

The right planning on-board inspection and maintenance is especially important on ships. At sea the conservation of the value of the ship and the freight is the responsibility of the crew. Therefore, crew members must operate in an extremely complex technical and environmental system.

In general, inspection and maintenance operations on ship have to be done according to the requirements of the IMO, the certification society, the harbor authorities and the manufacturer's service manuals.

The EU directive 94/57/EC, amended by 97/58/EC and 2001/105/EC regulates the standards for inspection and supervision organizations [39–41].

13.5.1 Maintenance Concepts

Inspection focuses on the reliability of individual machines according to the Reliability Centered Maintenance (RCM) system or on the calculation of risk according to the Risk Based Maintenance (RBM) system [42, 43].

On ships there is a difference between maintenance based on time and on condition [44]. Maintenance based on time means that after a fixed runtime, components have to be replaced. Maintenance depending on condition does not set the overhaul time intervals, but it depends on the quality of the components.

There are three classes of ship maintenance:

  • Corrective;
  • Preventive; and
  • Predictive.

Corrective maintenance is a repair to the system after failure if necessary. Preventative maintenance involves the replacement of parts, adjustments of the system or changes of the system to improve the reliability of the system and prevent failure by staving off the effects of system aging. Predictive maintenance requires the assessment of the system by a system expert and unscheduled maintenance has to prevent the possibility of the failure based on unrevealed system problems. Enforcing predictive and preventive maintenance is most effective, as the timely replacement or repair of a defective subsystem. Well organized prevention is less costly than the loss in revenue caused by an inoperative ship [45].

The definition of the maintenance intervals requires an exact knowledge of the influence of different loads, operating conditions, and wear and tear of ship components. At this field, extensive checking and test stand examinations with experiments are necessary. Life cycle is important criterion for the sustainability of a component and for its efficiency during operation. This time can be determined by on-board monitored signals of the main engine and the auxiliary equipment. Marine engine manufacturers usually specify the maintenance intervals for certain motor types based on the amount of fuel consumed and pollutants emitted [46].

The load of a ship crucially determines the life span of the engine and the auxiliary parts. Life cycle is determined by the number and the amplitude of load changes. This can be done using a data recorder and a diagnostic system [47].

Monitoring operation conditions determines the amount and the kind of maintenance. Data monitoring systems can estimate the reasons and the consequences of higher fuel consumption and exhaust gas emissions. Classification and examination institutions increasingly define the maintenance intervals for certain types of engines depending on the fuel consumption and exhaust gas emissions, and the frequency and the seriousness of error messages reported by the on-board micro controller system.

13.5.2 Crew's Responsibility

In inland shipping, specialists can be brought in. At sea, the crew does the inspection and operates the diesel engines, pumps, compressors, steam generating units, cooling systems, fresh water plants, fire-extinguishing systems, electric and computer plants, etc. The crew has an increased responsibility because of the increasingly complex technology on board [48].

Fuel accounts for 20–40%, in specific cases for 40–60% of an average shipping company's total operating costs [49]. Therefore, fluctuations in oil prices directly influence earnings. Fuel and exhaust gas emission saving measures adapted for energy conservation and profitability are the most important tasks. In the future, exhaust gas emissions devices can be effectively controlled not only with on-board measurement technology but also by using remote sensing methods.

The working efficiency of mechanical and electrical equipment has a direct impact on the fuel consumption, on the maintenance, and on the efficiency. Nowadays, crew members must not only navigate ships, but must be able to adjust the angle of fuel injection to the right position to reduce the lag time for ignition and improve heat efficiency. Cleaning the air inlets and exhaust gas outlets can also decrease fuel consumption and exhaust gas emissions by 2–3% [50].

Periodic checks of cylinders improve the timing of the valves and the injection pressure, the mechanism of the fuel pump, the plunger coupling, the fuel injector spring, and the needle valve coupling. Failures in the central elements of the engine can cause a serious increase in fuel consumption and exhaust gas emissions. Preventions hinder wear of components in the combustion chamber, e.g., air leak which usually leads to damage to cylinders, pistons, and piston rings [51].

The maintenance of the lubrication system reduces mechanical friction and wear. It is important to raise the cooling water temperature of diesel engines to 65–90C (149–194F). Fuel is not optimally used at low temperatures, because higher fuel viscosity increases the friction and resulting wear of parts. Preventing oil leaks, especially at the connection of the oil injection and return line, improves fuel efficiency [52].

Optimal use of waste heat helps to decrease fuel consumption [53]. About 40% of all the heat generated is turned into the output power, while the rest is lost outside of the ship through heated fuel tanks and pipes, exhaust gases, and cooling water [54, 55].

Fuel consumption is also decreased through careful maintenance of the turbocharger, by periodic cleaning of the air filters and removing soot from the exhaust gas [56].

Besides technology, the economical plan of the routes and the shipping schedule are decisive for fuel consumption as well as for exhaust gas emissions. The choice of the most efficient port for avoiding congestion and having optimal connections to road and rail transportation are also decisive. Routes should be optimized according to the sea conditions and to the weather which strongly shortens or extends the journey distance and time. Efficient navigation helps to avoid unnecessary detours and dangerous situations. Rational use of ocean currents and winds also reduces fuel consumption.

Modern telecommunication and Internet provide topical information about traffic. This makes it possible to avoid creating bottlenecks at water ways and in harbors, and enabling rational storage of goods. Freight transportation usually needs cargo for the return trip. Shipping companies cooperate in purchasing fuel. Energy conservation management and the proper handling of waste oil usually conserve 1–3% of fuel [57].

Ships in harbors are more and more switching to shore power and replacing their shipboard generators to save fuel and exhaust gas emissions near environmentally sensitive areas [58].

13.6 Summary and Recommendations: Inspection and Maintenance

Optimal operation of vehicles, airplanes and ships depends on a variety of parameters. Inspection of engines requires highly developed on-board monitoring methods to control the quality of engine, propulsion and safety systems. A maintenance schedule with adequate training can increase safety and reduce costs

13.6.1 Vehicle Technology

OBD is the indirect monitoring of the combustion and the emission systems. The first systems were developed in the 1980s for the continuous inspection of vehicles. Today, a malfunction can be precisely recognized by logical evaluation of individual sensor values and by comparison of the measured values with stored reference data of the operating point.

In exactly defined check routines, the OBD system starts periodic tests for monitoring the quality of controlled elements with sensor signals. Since the introduction of OBD, manufacturers are obliged to uniformly define and store malfunctions and to transmit MIL signals to the interface of the system.

Preventive maintenance and repairs are vitally important for vehicles to ensure that they operate reliably. In well maintained vehicles, repairs are done only if a component fails by external influences.

13.6.2 Airplane Technology

The inspection and maintenance plan is carried out according to internationally agreed guidelines. Inspection programs should be approved by the aviation authority of the state of registry. Individual actions are summarized in packages or during inspections. The operator has to continuously check the airworthiness and to report on the fuel consumption to the management.

The development of inspection and maintenance programs for a new airplane begins approximately two to five years before its production. Close cooperation between airplane manufacturers and operators is important for the development of its Maintenance System Guide (MSG). The comprehensive MSG-3 system identifies more than 3,000 parts. Nowadays the volume of modern maintenance plans requires an electronic storage capacity of more than 1 GB.

Improved inspection and maintenance activities decrease costs in both civil and military aviation. New methods in maintenance technology are very often introduced in military jet airplanes first. A positive example is the increase in the maintenance interval with the automatic control system Engine Enhancement Package which lowers the life time maintenance costs by about 30%.

13.6.3 Ship Technology

Each manufacturer establishes its own individual inspection and maintenance documents. Experience shows that monitoring ship operation positively affects the costs during the ship's entire life.

Beside the maintenance and repair manual, there is also a list of replacement parts. It specifies which modules must be replaced after certain time periods of engine operation.

The results are definitions of required maintenance which are usually described in the job cards. Electronic or paper card systems usually contain the number and the qualification of the workers, the lists of the necessary tools, the set-up times, and the safety requirements for the ship.

The engine document lists only original parts for replacements. Using unauthorized parts for maintenance or for repair invalidates the guarantee and the confirmation of the Type approval.

References

References 207

  1. Diesel particulate and occupational health issues. http://www.aioh.org.au/downloads/ documents/PositionPapers/AIOH\_DieselParticulatePositionPaper.pdf

Chapter 14 Navigation

The word ''navigation'' historically means the art of the steering a ship. Therefore, changes in operation are related to the route and the journey. Today, navigation is a widely used method for the optimal regulation of traffic on roads, water, and in the air. There are two preconditions for modern navigation [1]:

  • Precise determination of the vehicles', airplanes', and ships' position; and
  • Knowledge of the best routes to the planned destination under current conditions.

Navigation consists of different elements in road traffic, in aviation, and in shipping, but the basics are similar in all types of transportation.

14.1 Road Transportation

On the road, vehicle navigation uses an integrated telecommunication system based on computers, also known as Information and Communication Technology or Telemetric Technology [2]. This system sends, receives, and stores information via wireless telecommunication devices. The position of vehicles, similar to other types of transportation means such as airplanes and ships, is determined by Global Positioning System (GPS) [3]. The main elements of the GPS system are satellites in space with antennae. All means of transportation have a micro antenna, to send and receive signals to and from satellites.

Corresponding measuring devices are built into waterproof boxes and installed at ground level in several positions, e.g.,

  • As optical sensors over roads, pavements or crossings at traffic lights, hanging lamps, or on traffic signal posts;
  • As induction wire coils in the asphalt on roads; and

210 14 Navigation

Fig. 14.1 Sensors for navigation at a crossing

Fig. 14.2 Methods of navigation in road transportation

• As on-board navigation systems in vehicles; see Fig. 14.1 [4].

Telemetric systems in road transportation intensively include fleet management and complex technology for optimizing driving, health and safety conditions; see Fig. 14.2 [5].

Experience shows that better navigation effectively saves fuel and exhaust gas emissions. When drivers in Europe travel more than 20,000 km (12,420 mi) a year in regions with high traffic density and high population, optimal navigation can save a distance of 2,500 km (1.553 mi) a year [5]. This equals to approximately 12% of the entire annual fuel consumption. Navigation systems are especially useful in traffic jams, in that drivers save up to 20% of fuel if they continuously use information from the Traffic Message Channel [6].

14.1.1 Ecologic Strategy of Navigation

Navigation systems help to find the fastest way to a certain destination. New systems calculate not only all possible ways but also the routes with the shortest direction and the smallest fuel consumption across the field [7].

Route calculation improves services and profits and protects the environment. Trucking firms usually use a special algorithm for the calculation of the most economically optimal and least polluting route. This technology offers enormous profit potential for trucking services. High capacity computers determine the optimal route within milliseconds. Saving fuel means decreasing CO2 and pollutant emissions and also a decrease in other pollutants. Self Diagnosis system can support ecologic navigation in a network due to communication between the vehicle and an electronic checkpoint.

Congestion in traffic including different accelerating and braking phases of a lot of vehicles leads to higher concentrations of exhaust gases in the local environment. Fuel consumption and exhaust gas emissions can be particularly effectively decreased if traffic light signals are synchronized. Other measures of traffic organization, e.g., the construction of modern roads, the removal of redundant crossings, etc., also contribute to lowering the specific fuel consumption and the specific exhaust gas emissions per road vehicle. However, optimally organized traffic conditions often lead to an increasing amount of traffic which usually causes more global fuel consumption and higher global pollution on reconstructed and renewed roads.

14.1.2 Foresighted Driving

Navigation supports not only the best route but also the choice of the optimal speed. Increasing the velocity of commercial vehicles weighing 25–40 t on roads in villages, cities, and highways leads to higher fuel consumption; see Fig. 14.3 [8].

Not only accelerating but also braking requires surplus fuel. Braking from 90 to 60 km h-1 (55.9–37.3 mi h-1 ) on a highway leads to additional fuel consumption of approximately 0.7 l (0.18 gal (US) and 0.15 gal (UK)) of diesel fuel. The time advantage of not driving with foresight is small, because basic traffic conditions strictly determine the time needed to the destination, independently from short accelerating and decelerating phases; see Fig. 14.4.

Higher than optimal speed leads not only to increased fuel consumption and exhaust gas emissions but also to more accidents. Fuel and emissions can be saved and unnecessary stops and goes can be avoided with foresight to recognize obstacles in time by observation and navigation [9].

212 14 Navigation

Fig. 14.3 Fuel consumption of mixed driving on country roads and highways depending on speed and load

Fig. 14.4 Differences between travelling with and without foresight

14.1.3 Convoy Travel with Heavy-Duty Vehicles

The average speed on highways is decreasing worldwide because traffic is generally becoming denser. For this reason, the automatic regulation of the driving speed on highways effectively saves fuel and exhaust gas emissions. One possible way is to structure heavy-duty vehicles into a convoy on the highway so that they drive in a line with automatic regulation without drivers except for the first vehicle [10].

Besides saving fuel, this system also contributes to the optimal use of the highway's capacity. The vehicles following behind the convoy would also save fuel; see Fig. 14.5 [11].

Fig. 14.5 Driving and leaving the convoy journey

Fig. 14.6 Measurement and communication in a convoy

Complex driving assistant and monitoring systems must control distance, speed, and direction in front of and behind the convoy and between the vehicles in the convoy; see Fig. 14.6.

Automatic driving assistant systems are still in the predeveloping phase. Current route planning systems already effectively save fuel. Drivers using trafficenabled navigation devices are spending 18% less time driving on an average trip versus drivers without navigation [12].

14.2 Navigation in Aviation

14.2.1 Airports and Aircraft Operators

Airport layout, the infrastructure, and the organized ground movement determine the distance and the time that an airplane has to travel between its parking position and the runway. This movement may unnecessarily increase fuel consumption on 214 14 Navigation

the ground. The length and the altitude restrictions for landing and the required turns for departure and arrival routes also influence fuel consumption. Planners who design departure and arrival routes have to consider alleviating noise over populated areas and the terrain and the airspace requirements of nearby airports [13].

The airline must also decide the construction of aircraft, the types of on-board equipment, the kind of license, and the rating of the pilots. On-board navigation equipment must match with the radio waves to the ground equipment along the flight path [14].

14.2.2 Information for Civil Aviation Personnel

No safe and efficient flight planning is possible without in-time knowledge of actual and forecasted weather and the present and expected state of the flight conditions along the route and during the flight. These facts influence fuel consumption and emissions in different ways [15].

The demand, the role, and the importance of aviation information have significantly changed with the evolution of:

  • Communications, Navigation, and Surveillance [16];
  • Air Traffic Management [17];
  • Area Navigation (RNAV) [18];
  • Required Navigation Performance [19]; and
  • Airborne Computer-based Navigation Systems [20].

In aviation the requirements for quality, accuracy, precision, and integrity of air traffic and terrain data are rising; see Table 14.1.

14.2.3 Air Traffic Control Services

Each nation maintains its own Air Traffic Service (ATS) services responsible for flights within its territory. The ATS system consists of flight information, alerts, air traffic advisory, and air traffic control (ATC) services.

No aircraft is allowed to enter into or operate within a controlled airspace unless it has ATC clearance, except for a few but strictly regulated cases. A flight is controlled when it is subject to ATC clearance. Over the high seas, the ATC services are provided according to regional agreements concluded by the nations involved.

There are generally three basic controls and some subdivision services in air traffic; see Table 14.2 [26].

ATC Services can be divided or integrated otherwise and further subdivisions can be established according to the traffic volume and to the density of structural elements, such as the airports and the airways. The terminal control of the airport

Table 14.1 Information systems in aviation

Information system Description
Weather information Aviation weather information observed locally is collected and
disseminated by the World Area Forecast System (WAFS) and by
national meteorological offices in a timely manner as printed reports
and weather charts [21]. The local observations are added to in-flight
observations by pilots and satellite data. Observations are made by
humans or automated weather stations, based on internationally
accepted methods, equipment and timing. The reports and forecasts
are also encoded as texts according to international standards
Aeronautical
information		 Information on the state of aviation infrastructure called ''aeronautical
information'' is published as a package by the nations for their
territories according to ICAO standards in Annex 15 Aeronautical
Information Services (AIS) on the manner and timing of promulgation.
Aeronautical Information Publication (AIP) and Notices to Airmen
(NOTAM) are the main elements of the integrated information package
[22]. NOTAMs are issued and distributed within aviation communities
through a dedicated communication network at all times. This
information should be available for the operator before takeoff and, in
some instances, must be provided during flight
Dangerous air traffic
incidents		 There is a mandatory system for pilots to report on dangerous air traffic
incidents and occurrences experienced during flight to the
appropriate Air Traffic Control (ATC) authority [23]. A report is due
if a near-collision could have been avoided, if prescribed procedures
cannot be complied to or if ground equipment and facilities failed.
An air traffic incident report serves the standardized fashion of
written records on circumstances and details. The pilot reports it by
radio if the incident occurred in-flight. At the first landing following
the incident within the shortest time period the pilot submits the
report to the nearest Air Traffic Services Reporting Office (ARO), or
if none is available, to the office of any Air Traffic Service (ATS) [24,
25]. ARO was established for the purpose of receiving reports
concerning air traffic services and flight plans

Table 14.2 Air Traffic Control services

Control services Description
Airport control
service		 Airport control service is responsible for the airport's traffic at and near
airport area. The airspace around the airport for a horizontal distance of
10–15 km (5.4–8.1 nmi) and an altitude of 1,000 m (3,279 ft) is
included in the controlled area. Furthermore, it may include tower
control, ground control, clearance delivery and other units
Approach control
service		 Approach control service is responsible for the departing and arriving
flights of the airport along designated corridors between the airport and
the airspace border of an area control service
Area control
service		 Area control is responsible for controlled flights within controlled airspace,
generally along the cruise portion of flights. An example is the
overwater portion of flights between the continents, where Oceanic
Control Areas (OCA) are designated and oceanic control centers are
responsible for control [27]. These regions are mainly without radar
coverage

216 14 Navigation

and possible subdivisions is responsible for the control of confluenced routes in the vicinity of the airport which covers an area, typically 50–80 km (27.0–43.2 nmi) around the airport [28].

In addition to its basic functions, ATC may provide weather advisories, terrain information, navigation assistance, and other services to pilots. ATC is vital for maintaining separation between aircraft flying at high speed in congested areas and bad weather when pilots are unable to see the environment and for avoiding distances to other aircraft that are too small [29, 30].

14.2.4 Weather Conditions and Airport Operating Minima

In the beginning, landmarks were the only way for pilots to safely navigate. The pilot had to see other airplanes in order to avoid collisions. Clouds, fog, and other weather conditions restricted a pilot's sight. Therefore, safe flying required that limits of visual conditions had to be established.

Airport operating minima expresses the weather limits of the usability of an airport for takeoff, landing in a precision approach, or landing in a non-precision approach. The terms used are ''visibility'' or ''runway visual range'', ''decision altitude'' or ''minimum descent altitude'', and, if necessary, ''cloud condition'' [31].

Each participant, the airport, the airplane, and the pilot has its own minima. Airport minima depend upon the available approach facilities. Aircraft minima are based on on-board equipment. The personal minima of a pilot are determined by his experience. The least favorable of these minima should be applied in practice, including any increments required due to system failures.

14.2.5 Flight Rules

Flight rules play an important role in planning and carrying out fuel efficient flight, for example through eliminating uncertainties that would otherwise increase the need for surplus fuel. There are visual and instrument flight rules; see Table 14.3.

There are still minimum conditions and limits which must prevail so that takeoff or landing can be legally initiated. These conditions and limits vary according to weather conditions, location, and the height of terrain and obstructions in the vicinity of the airport, the available equipment of the aircraft, and the qualification of the crew [35].

Key factors in alleviating, the load on the environment besides expediting traffic flow are good control practices creating airspace design with airways as straight as possible, and new concepts such as Free Route Airspace Concept for free flying areas [36]. There are specific airspaces within which users can freely plan their routes between an entry point and an exit point, without references to the ATS route network. In these airspaces, flights remain subject to ATC. Consequently and

Table 14.3 Flight rules

Type of rules Description
Visual flight rules
(VFR)		 VFR is the set of rules that apply to an aircraft that navigates solely by
visual references [32]. Spatial disorientation or collision with ground
and obstacles may occur when a pilot continues VFR into instrument
conditions
Instrument flight
rules (IFR)		 IFR regulates the procedure for flying in weather conditions below VFR
weather minimums [33]. IFR has rules for pilot ratings, pilot
controller communication procedures and radio navigation procedures
Safety aspects The main purpose of IFR is to ensure safe flights by enabling precise and
reliable determination and tracking of positions even in Instrument
Meteorological Conditions (IMC) and either within or outside of
controlled airspaces and by clearly stating the environmental and
manmade limits, conditions and rules of operation [34]. Flying IFR in
ATC airspace increases safety and the controller provides safeguards
against collisions

independently from the routes inserted in flight plans, it can become common practice to offer aircraft operators the shortest routes.

Eurocontrol Airspace Concept ECAC includes:

  • The ''packaging'' of en route and terminal routes, optimized trajectories, airspace reservations, and ATC sectors into Airspace Configurations which are designed and dynamically managed together to respond flexibly to different performance objectives which vary in time and place; and
  • Airspace Configurations activated through integrated collaborative decisionmaking processes at national, regional Functional Airspace Block, and European airspace network level reflected in the Airspace Network Management component of the 2015 Airspace Concept [37].

14.2.6 Optimum Climbing Path and Flight Profile After Takeoff

The takeoff and the initial climb are the noisiest phases of a flight using the highest power at the airport and in its surroundings. Takeoff usually starts at the beginning of a runway with full thrust on the engines. If necessary, the thrust reduction is in accordance with the actual takeoff weight. The climbing path and profile following the takeoff can be optimized using modern navigation systems. The main phases of takeoff and climbing are presented in Table 14.4 [38].

The takeoff thrust can be tailored to the actual conditions. The pilot sets lower than the full thrust which the engine is able to deliver but enough thrust for safe operation in the actual conditions. This measure can conserve engine life and reduce fuel consumption and exhaust gas emissions and lower noise at and near airports.

218 14 Navigation

| Table 14.4 | | Takeoff flight path segments | |------------|--|------------------------------| |------------|--|------------------------------|

Path segments Description
First and takeoff
segment		 In general, the takeoff ends at a height of 35.2 ft (10.7 m) above the end of
the runway where the speed for safe climbing is attained. The fuel
consumption and the concentration of NO and NO2
have the highest
level in these phases
Second segment Takeoff is followed by a short climb with takeoff thrust settings meanwhile
the landing gear is retracted
Third and final
segment		 The third segment, started at a minimum of 400 ft (122 m) above field
elevation, is acceleration, performed in level flight to attain the final
segment at climbing speed, during which the flaps and slats are retracted
and thrust is cut-back. The final segment is a climb that generally ends
at 1,500 ft (457.5 m) above the field elevation

There are noise abatements in practice for takeoff and climbing procedures. Many airports publish departure routes indicating noise-sensitive areas along the flight path with the corresponding altitude and routing restrictions for the airplanes [39].

14.2.7 Descent and Approach Path Optimizing

The Flight Management System of a modern airplane automatically optimizes the flight profiles including the descent and approach segment profile [40].

Continuous Descent Approach (CDA) also has advantages for the reduction of fuel consumption, and noise and gaseous and particle pollution affecting residents around the airport. Instead of stepping down on a virtual stair the airplane glides with no flaps or with partially extended flaps. Full flaps and landing gear are extended only in the final segment of the approach. CDA can be started right at the end of the cruise portion of a flight, at the start of an arrival route, or at a start of an approach procedure depending on the circumstances, i.e., traffic controller's knowledge, available airspace for separating the traffic, etc. [41].

The pilot can check the distance to the airport using Distance Measuring Equipment, if available, while the controller can supervise the progress of the flight by radar [42].

14.2.8 Fuel Saving by Improved Airspace Coordination and Air Traffic Organization

Eurocontrol, the European Organization for the Safety of Air Navigation, estimates that 1.5 9 106 t (3.3 9 109 lb) of fuel are still unnecessarily lifted into the air every year because airplanes must be able to divert from their planned destination. About 1% of all European aviation emissions, corresponding to 0.63 9 106 t (1.39 9 109 lb) CO2 emissions per year, could be saved through improved methods [43].

Improved coordination is required between civilian and military users concerning the daily use of airspace blocks in order to avoid airspace congestion and to increase fuel savings.

Through reforming flight navigation, airspace organization, and ATC, the aviation industry could reduce fuel consumption by 15%.

In the European Union, the ''Single Sky'' initiative started in 2008. EU researchers demonstrated new technologies on a large scale within the SESAR initiative. According to the aims of the Advisory Council for Aeronautics Research, the fuel consumption and the CO2 emissions in European aviation should be reduced by 50% by 2020 compared with the year 2000. NO and NO2 emissions should be lowered by 80% and noise output by 50% [44].

14.3 Ship Navigation

Planning of marine transportation involves freight and business conditions. Navigation in shipping is the process of steering a ship from one harbor to another. The quality of navigation highly influences fuel consumption and exhaust gas emissions. Nowadays, the navigation system determines the position of a ship by collecting information from satellites [45].

Figure 14.7 shows the main influencing factors for ship navigation [46].

IMO guidelines define appraisal, planning, execution, and monitoring of the voyage which are parts of the passage and navigation planning and are reflected in the local laws of IMO signatory countries [47].

Navigation planning comprises a complete description of vessels from the start to the finish of the voyage. The plan includes leaving the dock and harbor, the end route portion of the voyage, and the approach to the destination. According to international law, the vessel's captain is legally responsible for navigation planning, but on larger vessels, the task is usually delegated to the navigator [48].

The appraisal stage deals with the collection of information relevant to the proposed voyage as well as fuel consumption and exhaust gas emissions. In the execution of the voyage, the navigation plan takes all special circumstances into account, e.g., changes in the weather which may require the navigation plan to be reviewed or altered [49].

14.3.1 Shipboard Routing Assistance

Shipboard Routing Assistance (SRAS) increases the safety of the ship and reduces the risk to the ship and its cargo. With SRAS the officers on the bridge can 220 14 Navigation

hull resistance (cleanliness, design factor, load of deck with containers, exhaust gas after treatment (with CSR and filter technology)

air conditions
vessel conditions		 fuel conditions water conditions
t
p
h
w
wD		 temperature
pressure
humidity
wind power
wind direction		 v
D
a
g
rpm		 speed
direction
acceleration
gear choice
number of revolutions		 v
De
F
S		 viscosity
density
flaming point
sulphur content		 Wa
WD
St		 wave amplitude
wave direction
streaming

Fig. 14.7 Main influencing factors for ship navigation

immediately recognize and monitor weather and dangerous operating conditions and can start corrective measures if necessary [50].

The ship's speed, wave direction, and wave heights are continuously measured by radar and compared with databases of the voyage. Forecasts can be calculated for the current ship movements in the on-board computer.

14.3.2 Ship Distress and Safety Communications

Global Maritime Distress and Safety System (GMDSS) is an integrated communication system using satellite and terrestrial radio communication to ensure aid for ships in distress [51]. GMDSS communicates with protocols to increase the safety and assist in the rescue of distressed ships. The Maritime Safety Information system provides meteorological and navigation information anywhere at sea [52].

All passenger ships and cargo vessels over Gross Tonnage (GT) 300 t, i.e., 661 9 103 lb on international voyages must comply with GMDSS. Vessels under 300 GT, recreational, and offshore ships are not subject to GMDSS requirements, but they increasingly use Digital Selective Calling (DSC) VHF radios [53]. Regulations governing GMDSS are contained in the International Convention of SOLAS [54].

DSC is a part of the GMDSS. It automatically sends a digital distress signal identifying the calling vessel and the nature of the emergency with the help of Maritime Mobile Service Identity which can identify ships and coastal stations [55].

Ship distress and safety communication contributes to optimal fuel consumption and exhaust gas emissions. The system does not yet give direct information on fuel management, but informs the captain and officers about all conditions which can influence the maneuvering a ship [56].

14.3.3 Meteorological and Oceanographic Coordinator and Supporting Service

The world's oceans are divided into 16 areas of responsibility for broadcast purposes called either Metareas for meteorological information or Navareas for navigational warnings. The Area Meteorological and Oceanographic Coordinator (AMOC) and the Supporting Service must provide [57]:

  • Basic meteorological forecasts; and
  • Warnings tailored for specific areas.

The service may also include:

  • Basic oceanographic forecasts for the concerned areas;
  • Observing, analyzing, and forecasting of meteorological and oceanographic variables required as input for models describing the movement, dispersion, and dissolution of marine pollution; and
  • Operating these models and accessing national and international telecommunication facilities [58].

This information may be prepared by AMOC, another supporting service or by a combination of both. The authority responsible within the designated Marine Pollution Incident must receive information about the location and details of any marine pollution or emergency response operations [59].

14.3.4 Broadcast for Navigation

The combination of Automatic Identification System (AIS) and beacon technology can be provided as a backup system to make navigation more reliable [60]. AIS transponders continuously transmit a vessel's position, course, speed, and other data to all other near-by ships. In ship-to-shore mode, coastal surveillance is important. Many countries deploy automated AIS base stations ashore to monitor the movement of vessels in their adjacent waters and to navigate ships on inland 222 14 Navigation

waterways. In ship navigation, developments make it possible to introduce specific navigation centers, similar to aviation.

AIS VHF transmission can ensure uninterrupted Differential Global Positioning System (DGPS) availability, even in severe weather conditions or with high interference. AIS information is collected with additional signals from radar, echo locators, and sonar [61].

Signals of all sensors could be displayed on a monitor of the bridge. The integration of Self Diagnosis service with AIS base station broadcasts could save costs for fuels and future fees for exhaust gas emissions.

14.3.5 Reporting Environmental Damaging Incidents at Sea

Exhaust gas emissions and fuel consumption do not yet belong to the control parameters of AMOC. However, the rising prices of marine fuel and the heightened emission regulations could lead to the measurement and reporting of both parameters [62]. An electronic Fuel Marine Monitoring device could discover deteriorations, wear in the combustion, in the exhaust gas after treatment system, in the auxiliary devices, and also in the propulsion, regulation, and steering system and send the message to the ship's owner so that management can reduce fuel costs and increase the operational efficiency [63].

Figure 14.8 presents the main elements of ship's navigation.

14.4 Summary and Recommendations: Impact of Navigation on Fuel Consumption and Emissions

Transportation is based on two main fields:

  • Worldwide navigation; and
  • Reasonable fuel prices for road traffic, aviation, and maritime shipping.

The efficiency of transportation strongly depends on the quality of navigation. Data and information for optimal navigation are transmitted via a worldwide communication net.

14.4.1 Vehicle Navigation

Road traffic uses telemetry to continuously organize traffic flow. Navigation systems have electronic, magnetic, or optical sensors and wires installed in measurement and operating equipment.

Fig. 14.8 Elements of ship's navigation

Sensors installed in roads and on vehicles communicate with each other. Data can be sent via GPS, Global System for Mobile communication, and Short Message Service to a telemetry center controlling the traffic.

The combination of on-board sensors with satellite systems is gaining influence. Organization measures for the continuous flow of traffic, e.g., intelligent ''green wave'' in variable road intersections and the introduction of environmentally friendly road pricing and on-board measurement in traveling vehicles can improve road navigation.

In the future wireless units could be built into vehicles and at traffic lights and emergency call boxes along the road. Sensors in vehicles and at fixed locations, as well as connections to wider networks, could provide information to drivers. The range of radio links could be extended by forwarding messages along highly frequented paths. Drivers could use this information to reduce the chance of collisions, to avoid bottlenecks, and to decrease the rate of fuel consumption and emissions.

14.4.2 Airplane Navigation

Current airspace has a density four times higher than 20 years ago. Safe and efficient flight has been gaining more and more importance. Starts begin with 224 14 Navigation

careful preplanning through taking data and information about the environment and infrastructure into account. Inflight data exchange between the dispatcher, pilot, and controller requires automated processes based on computer technology.

Traditional ATC practices need changes, i.e., good practices, in the first line:

  • Allowing directs airspace designs with airways as straight as possible; and
  • New concepts with free flying areas.

Optimal takeoff and climbing paths and CDA are key factors in alleviating the load on the environment.

Radio and satellite navigation has brought about better position recognition and tracking. With modern navigation, the advanced aircraft systems can optimize flight profiles and provide even more benefits from computers.

14.4.3 Ship Navigation

Methods of ship navigation have greatly changed. New procedures enhance the ability to complete the voyage and save fuel.

Coastal networks are established or are planned in Europe, North America as well as South-East Asia, India, China, Korea, Japan, South Africa, and several other countries. Similar networks are also planned along major inland waterways. A coastal AIS will soon replace the current DGPS beacon stations. It will not only provide frequent determination of position relative to geographic coordinates but also report the hydrographic features in restricted waters.

Fuel consumption and exhaust gas emissions monitoring completed with other operation parameters has become possible with GPS navigation in combination with data transfer to route management centers.

References

References 225

  1. Entwicklung und Untersuchung von Fahrerassistenzsystemen für elektronisch gekoppelten Lkw-Konvoi. https://www.zlw-ima.rwth-aachen.de/intern/seitenaendern/ldb/downloads/ 1788.pd

226 14 Navigation

  1. Noise Mitigation for Airport Growth. http://www.wyle.com/ServicesSolutions/science/ EMMA/AcousticandVibrationConsulting/Resources/DocumentLibrary/WyleReports/Pages/ nmag-T8.aspx

Chapter 15 Climate and Environmental Protection

The air of the Earth can be divided into different layers, which are defined through clear temperature differences. The two lower layers are important when referring to climate change:

  • 1. The troposphere, the layer with weather events and
  • 2. The stratosphere, the layer above the troposphere [1].

The upper limit of the troposphere varies daily and mostly depends upon the season and geographical latitude. In the area of the equator it is at an altitude from 16 to 18 km (from 52,459 to 59,016 ft or 9.94 to 11.19 mi), at the poles it is from 8 to 12 km (from 26,230 to 39,344 ft or 4.97 to 7.46 mi). In the tropopause between the troposphere and the stratosphere the temperature is approximately -60-C (-76-F). The ozone O3 layer is in the stratosphere at an altitude from 25 to 30 km (from 81,967 to 98,361 ft or 15.5 to 18.6 mi) [2].

The climate has been rapidly changing because of the rise in the concentration of CO2 and other Green House Gases (GHG) in the atmosphere. Global warming on the Earth is the result of emissions of CO2 and other climate changing gases [3].

15.1 Transportation Emissions

CO2 is the most important Green House Gas that originates from the burning of hydrocarbons, decomposition of biomass, e.g., from plants as well as from the respiration processes of humans and animals. The combustion of 1l (0.264 gal (US) and 0.220 gal (UK)) of gasoline produces 2.33 kg (5.14 lb) of CO2. The combustion of 1 l of diesel or kerosene emits 2.64 kg (5.82 lb) of CO2. The concentration of CO2 in the air is currently 370 ppm and increasing. CO2 remains in the atmosphere for approximately 100–200 years, depending on the concentration [4].

The worldwide CO2 emissions increased from 22,500 9 106 t (49,606 9 109 lb) in 1991 to 30,892 9 106 t (68,108 9 109 lb) in 2009. Despite the economic crisis between 2007 and 2010, the average worldwide emissions increased and will continue to rise in the next few decades. On the other hand, CO2 emissions have declined in many countries because of the economic crises in recent years [5].

Water vapor, H2O, is the most important greenhouse gas beside CO2. Without the naturally originating vapor from water, the Earth's surface would be approximately 20-C (68-F) colder. Unlike CO2, the water vapor emissions caused by humans are too small in relation to the natural evaporation on the Earth to influence the climate [6, 7].

Natural sources of nitrogen oxides, such as NO, NO2 and other nitrogenous substances, are caused by lightning and microbes in the ground. However, improvements in fuel efficiency have been achieved through the development of modern internal combustion and jet engines, which operate at higher temperatures and higher pressures than in the past. Unfortunately these improvements also increase the formation of nitrogen oxides, which can be reduced through further changes in the combustion chamber or in an appropriate exhaust gas after treatment system [8].

Unburned hydrocarbons, HC, are mixtures of several hydrocarbons which remain after incomplete combustion processes. The concentration of HC emissions depends on the load of vehicles, airplanes and ships. HC is a climate gas with a GHG factor that is three times higher, than CO2. At ground level, they contribute to the formation of summer smog [9].

Ozone, O3, is a three-atomic oxygen molecule. At ground level, ozone is a component of dangerous summer smog. At higher altitudes of the stratosphere, O3 molecules filter dangerous UV radiation [10].

While road and maritime transportation contribute to the summer smog near ground level, aviation contributes to the ozone hole in the stratosphere. Pollutants, such as NO2 reduce O3 concentration at ground level and lead to highly dangerous and unhealthy situations, initially in big cities. Smog decreases the O3 concentration at the poles by 2–4% in the winter and 4–8% in the summer.

Sulphur dioxide, SO2 molecules are dangerous to human health and form acid rain. In addition, SO2 is an important aerosol creator and lowers the temperature of the atmosphere through dispersion of sunlight. The climate role of SO2 is not yet completely clear [11].

Transportation will grow very intensively over the next few decades in comparison to other sectors of the economy, especially in the rapidly developing countries; see Fig. 15.1 [12].

The most meaningful international goals are:

  • Increasing independence from fossil fuels;
  • Decreasing climate gas emissions;
  • Minimizing the cost of alternative fuels;
  • Increasing the efficiency of road vehicles, airplanes and ships;
  • Supporting new financial investments; and
  • Creating new jobs for climate protection.

Fig. 15.1 Total Green House Gas emissions in developed and developing countries

Fig. 15.2 Interaction between the climate and the transportation

15.2 Interaction Between Climate and Economy

In the past, industrial production influenced the climate, but the relationships have changed and climate change is very intensively influencing transportation today. There is a clear interaction between both systems; see Fig. 15.2 [13].

15.3 Climate Protection in Road Transport

CO2 emissions from transportation have an impact on the climate and pollutants have an impact on the environment, and the human and the animal health. In contrast to solids and liquids, gases mix their substances very fast. The long decomposition time of GHG substances of approximately 100–200 years leads to the homogenous mixing of gases in the air. Exhaust gases from vehicles and ships,

Table 15.1 Regulation of emissions of Green House Gases in road traffic in the world

Country Regulation
China China introduced limits on CO2
emissions in 2005, 2008, 2009, and 2011 to protect the
environment [15]. The Chinese regulations limit vehicle weight. High performance
vehicles with high fuel consumption will not be sold in China in the future. Next
steps are China 4 for self-ignition engines (gasoline propelled engines have been
regulated in 2011) and China 5 in 2012
Japan In June 2010, the Japanese government started a study of further CO2
requirements for
2020. Each manufacturer has to achieve fuel efficiency as a weighted average in
each weight class. Consumption has been determined on 10–15 and FC08 test
cycles. New Regulation 2015 Fuel Economy will consider diesel and gasoline
vehicles together [16]
USA Moderate Corporate Average Fuel Economy standards are valid for fleet consumption.
Energy Independence & Security Act of 2007 estimates introduction of renewable
fuels and consumer protection [17]. EPA and NHTSA proposed new fuel economy
and GHG regulations for vehicles in 2009. Progressive proposals such as the
SULEV 20, SULEV 50, and SULEV 70 to update them are being advanced by the
CARB [18]. This regulation was valid for private vehicles, with less than 12 people
emissions from 205 g km-1 (7.231
oz km-1 or
and achieved a reduction in CO2
11.635 oz mi-1
) in 2000 to 180 g km-1 (6.35
oz km-1 or
10.217 oz mi-1
) in
output to 125 g km-1 (4.409
oz km-1 or
2008. The agenda is to lower the CO2
7.094 oz mi-1
) by the year 2020. Light Duty Trucks (LDT B 8,500 lb (3.8 t)) emit
about 250 g km-1 (8.818
oz km-1 or
14.188 oz mi-1
) presently. By 2020, that
should be reduced to 200 g km-1 (7.055
oz km-1 or
11.351 oz mi-1
)
EU European legislation requires decreasing fuel consumption and CO2
output [19]. The
middle performance category of private vehicles in the EU produces about
km-1 (5.608
oz km-1 or
9.023 oz mi-1
159 g CO2
) with an average consumption
of 6.6 l 9 100 km-1 (42.73
mpg (US) and 35.61 mpg (UK)). CO2
emissions are
limited to 130 g km-1 (4.586
oz km-1
, or 7.379 oz mi-1
) in 2015. 65% of the fleet
of cars must meet the requirement by 2012, 75% by 2013, 80% by 2014, and 100%
by 2015. After 2015, it should be decreased to 120 g km-1 (4.233
oz km-1 or
8.811 oz mi -1
) and to 95 g km-1 (3.351
oz km-1 or
5.392 oz mi-1
) by 2020. The
decision about how to reach the objectives for 2020 must be prepared in 2014

15.3.1 Legislation and Regulations

CO2 emissions depend firstly on the weight and the power of vehicles and secondly on the driving behavior of drivers and the traffic organization. Therefore, many governments regulate the weight and emissions of vehicles. Yet these standards are not easily comparable, due to differences in policy approaches, test drive cycles and units of measurement.

15.3.2 Comparison of Regulations

The relevant stringency and implementation years of fuel economy and GHG emissions standards in the world are in Table 15.1.

Fig. 15.3 CO2 emission limits of cars in the EU

Emissions of pollutants can be mainly decreased by increasing the efficiency of engines, the gears and reducing the weight of vehicles. Installing solar cells on top of cars can moderately decrease emissions by 7 g km-1 (0.247 oz km-1 , i.e. 0.397 oz mi-1 ). Further expected innovations will decrease emissions by 10 g km-1 (0.353 oz km-1 or 0.568 oz mi-1 ) by 2015; see Fig. 15.3.

In 20 years, the number of cars on the world is expected to go from one to two billion and the amount of energy used for transport will also double by 2050. The goal of the International Council on Clean Transportation (ICCT) is to protect public health, minimize climate change and improve quality of life for billions of people as the world's transportation infrastructure grows. ICCT consists of about 30 government officials and policymakers from the 10 largest motor vehicle markets—which together account for 85% of the world's new car and truck sales—and providing them and other interested parties with accurate information about research, best practices, and technical resources for improving the efficiency and environmental performance of cars, trucks and other vehicles, so ICCT helps accelerate an urgently needed transition to sustainable transportation [20].

15.4 Climate Impact of Aviation

The environmental aim of flight profile, airspace and airway optimization is to minimize climate changing emissions. However, up to now, flight altitudes and routes are optimized according to the weather conditions, the traffic situation and safety aspects, fuel consumption and costs, and not climate protection. Normally, the formation of condensation trails and cirrus clouds can be avoided by not flying through cloud and vapor saturated air masses. This is important for lessening greenhouse effects. Altitude and route optimization is frequently restricted by severe weather phenomenon. Aircraft adaptation to this phenomenon would bring more penalties than gains [21].

The purpose of optimizing flight routes is to avoid critical atmospheric zones by changing the altitude or the route of the flight to minimize climate changing emissions. New turboprop jet engines fly at altitudes between 7,000–8,000 m (22,951–26,230 ft) and produce the least damage to the environment and the climate. Despite its economic advantages, the very limited airspace limits the use of this altitude, especially in Europe and North America [22].

The altitudes of flight influence fuel consumption and emissions. In flights, the formation of condensation trails and of cirrus clouds can be avoided by flying at altitudes in the troposphere. However, at such altitudes the aerodynamics of airplanes and the efficiency of engines deteriorate due to the denser air, which increases fuel consumption by about 4% and lengthens flight times. At lower altitudes the takeoff and the approach time is shortened and the fuel consumption is decreased in the ascent and in the descent [23].

The impact of exhaust gas on the climate is different at different altitudes. At higher altitudes H2O and NOx emissions increasingly impact the climate, CO2 emissions have a decreasing impact; see Fig. 15.4 [24].

The type of the fuel also determines the climate impact of airplanes. The comparison of kerosene and hydrogen fuel shows different effects in the atmosphere; see Fig. 15.5.

Hydrogen significantly reduces negative climate impacts of combustion gases in comparison to kerosene at all altitudes. However, hydrogen is more a solution for the long term climate protection due to the technological and economical difficulties.

15.4.1 Trading with CO2 Emissions in Aviation

A trip from Europe to the east cost of the USA emits about 674 kg (1,485 lb) of CO2 per passenger (between Hamburg and New York). Aviation is responsible for 2.4% of the global CO2 emissions, but consumption and CO2 emissions will increase to 3 or 4% in 2050, in spite of expected improvements in the SFC [25].

The accelerated introduction of more modern aircraft would reduce emissions per passenger-kilometer. Other opportunities arise from the optimization of airline

Fig. 15.5 Climate impacts of combustion products in the atmosphere

timetables, route networks and flight frequencies. Emissions can be further reduced by increasing loads, minimizing the number of empty seats and improved regulation of air traffic [26].

However, the total number of passenger-kilometers is growing at a faster rate than manufacturers can reduce emissions. At this time, there are almost no alternatives to burning kerosene. In the short term the growth in aviation is therefore likely to continue to generate an increasing volume of GHG emissions [27].

The IATA has the following environmental targets:

  • Fuel efficiency must improve by 25% in 2020 and by 50% in 2050 in comparison with 2005; and
  • 10% alternative fuels must be used in 2020.

Besides climate protection, aviation has two other environmental challenges:

  • Decreasing noise in air traffic; and
  • Improving the air quality on the ground, primarily reducing NOx emissions [28].

According to plans of the European Regional Airline Association (ERAA), the upper limit of pollutant emissions in air traffic must be 97% in 2012 and 95% in 2013 on the basis of the average emissions between 2004 and 2006. 15% of CO2 emission certificates must be auctioned off by 2013. Therefore, low emission airliners will have a cost advantage, while older airplanes with higher emissions will have to buy additional certificates [29].

The EU states which auction certificates must invest only in appropriate projects for climate protection. The roadmap of the EU plans to cut CO2 emissions by 60% by 2050. In addition, every state is obliged to transparently report its investment in climate protection.

Fig. 15.6 Connection between temperature of the ocean's surface and frequency of tropical cyclones

15.4.2 Impact of Climate Change on Air Traffic

The Earth's atmosphere absorbs 7% more humidity close to the surface per degree of warming. Feedback from local wind can increase humidity by up to 14%. This process leads to more tropical storms over sea and land, like hurricanes, cyclones and tornados; see Fig. 15.6 [30].

Wind velocities can reach 500 km h-1 (311 mph). Extreme precipitation events appear more frequently. In the northern hemisphere, the number of short, extremely intensive downpours is increasing. In summary, the number of storms is constant, but the number of severe storms with lightning strikes is increasing; see Table 15.2 [31].

Climate change strongly influences aviation. Cumulous clouds reach altitudes of 15–16 km (49,180–52,459 ft, i.e., 9.3–9.9 mi) with different electrical charges. Because of the wide area and the high altitude of storm clouds, airplanes flying in these air corridors do not have any possibility to fly over these zones.

Positively charged lightning is dangerous even several km from the actual thunderstorm zone at an altitude from 11 to 12 km (from 36,066 to 39,344 ft or from 6.8 to 7.5 mi). Their temperature is 30,000-C (54,032-F) in the lightning channel and their strike velocity is 100,000 km h-1 (62,150 mph). Although only 5% of all lightning is positively charged, it is more dangerous than negatively charged lightning because it has particularly intensive discharges with considerably higher current intensities and longer time intervals [32].

Some composite airplanes also have an additional layer of protection against lightning strikes by installing Metal Oxide Varistors (MOV) throughout the circuit. If an MOV senses a sudden surge of current than it is designed to break and protect the rest of the aircraft's delicate electronic systems [33]. Aircraft design principles

| Year | | Number of lightning strikes on earth's surface | | | | | |------|-----------------|------------------------------------------------|--|--|--|--| | | Absolute number | Specific number (number km-2
) | | | | | | 2004 | 1,752 455 | 4.9 | | | | | | 2005 | 1,927 941 | 5.4 | | | | | | 2006 | 2,484 791 | 7.0 | | | | | | 2007 | 2,662 409 | 7.5 | | | | |

Table 15.2 Number and density of lightning strikes in Germany

Table 15.3 Fuel consumption and CO2 emissions of non-military shipping

Sort of shipping Average values
2009
106 t
(109 lb)		 Average values
2020
106 t
(109 lb)		 Average values
2050
106 t
(109 lb)
Total ship fuela consumption 333 (734) 400 (882) 899 (1,912)
emissionsb
Total ship CO2		 1,019 (2,246) 1,428 (3,148) 2,751 (6,065)
CO2
emissions of maritime
shippingc		 843 (1,858) 1,012 (2,231) 2,276 (5,018)

and precautious operating procedures exclude nearly any in-flight emergency events happening due to severe weather phenomenon.

15.5 Climate Impact of Shipping

Maritime shipping emitted approximately 843 9 106 t i.e., 1,859 9 109 lb CO2 in 2009 and therefore contributed to 2.8% of anthropogenic CO2 emissions. In comparison, aviation presented a similar—if slightly smaller—annual emission rate with 733 9 106 t (1,616 9 109 lb) CO2 [34].

Sea-going vessels consume fuels with a sulfur content of 2–3% and annually emit (10–12) 9 106 t i.e., (22.03–26.45) 9 109 lb SO2 into the atmosphere. The production of SO2 is the reason that ships' emissions have a disproportionally high absorption of infrared radiation. According to the IPCC predictions, CO2 emissions in maritime shipping will increase by factors of 1.1–1.3 up to 2020 and by factors of 2.4–3.0 up to 2050. They are the most powerful rates of increase in transportation; see Table 15.3 [35].

In inland navigation, ships often use higher quality fuels, i.e., diesel fuel. Table 15.4 shows the current and future proportions of fuel consumption and emissions in inland shipping [36].

a Calculated excluding fishing vessels b Calculated including domestic shipping and fishing, but excluding military vessels c Calculated subtracting domestic emissions from the total emissions

| Fuel quality | Shipping quantity | | | | | | | |--------------|---------------------------|--------------------------|---------------------------|--------------------------|--|--|--| | | 2009 | | 2050 | | | | | | | Fuel
106 t
(109 lb) | CO2
106 t
(109 lb) | Fuel
106 t
(109 lb) | CO2
106 t
(109 lb) | | | | | HFO | 13.3 (29.3) | 40.2 (88.6) | 35.91 (79.2) | 108.5 (239.2) | | | | | MDO | 19.7 (43.4) | 61.0 (134.5) | 53.19 (117.3) | 164.7 (363.1) | | | | | Total | 33.0 (72.6) | 101.2 (223.1) | 89.10 (196.4) | 273.2 (602.3) | | | |

Table 15.4 Domestic fuel consumption and CO2 emissions

Table 15.5 Dependence of fuel consumption and emissions in maritime shipping on economy, transport efficiency and energy demands

Categories Variables Related elements Unit
Economy Demand Number of inhabitants,
local, regional and
global economic growth		 (t mi) year-1
Transport
efficiency		 Efficiency depending on
fleet composition, ship
technology and
operation		 Ship design, propulsion
advancement, vessel
speed, environmental
regulations, trade with
GHG emissions		 MJ (t mi)-1
Energy demand Carbon content in navy fuel Cost and availability of
fuels, use of residual
fuels, distillates,
biogenic fuels or other
fuels		 g (MJ)-1

Fuel consumption and emissions of fleets are determined by the economy, the transport efficiency and the energy demand of ships; see Table 15.5 [37].

Predictions have to consider all factors. For shipping technology, despite the greatest care, predictions contain inaccuracies and uncertainties.

15.5.1 Large Two-Stroke Marine Diesel Engines

Fuel consumption and CO2 emissions of large two stroke marine diesel engines can be examined at a test bench. In artificial conditions at a test bench, Best Specific Fuel Consumption (BSFC) corresponds to single operating points. The real SFC in operation is expected to be 10–15% higher than in test measurements, because:

  • An engine does not always operate at its best operating point;
  • The energy content of its fuel may be lower than that of the test bench fuel (residual fuels typically have heating values which vary ±5%); and
Energy supply Engine work kW
s-1
(BTU
)
SFC B5,000 5,000–15, 000 C15,000
(B4,739) (4,739–14,218) (C14,218)
g kWh-1 195–185 185–175 175–150
(oz BTU-1 ((20–19) 9 10-4 ((19–18) 9 10-4 ((18–16) 9 10-4
) ) ) )

Table 15.6 Marine engine's specific fuel consumption (SFC)

Table 15.7 Auxiliary engine fuel consumption

| Energy supply | Auxiliary engine work kW
(BTU s-1
) | | | | | |---------------------------|-------------------------------------------|---------------------------------|--|--|--| | SFC | C800
(C758) | \800
(\758) | | | | | g kWh-1
(oz BTU-1
) | 200–210
((21–22) 9 10-4
) | 210–220
((22–23) 9 10-4
) | | | |

• SFC values are given also with ±5% tolerance because of engine wear, ageing and sub-optimal maintenance of fuel injectors and injection pumps, deterioration of the propeller, defects in the turbocharger, increased filter resistances and wear and tear of the heat exchanger.

The SFC of the main engine depends on the performance of the engine; see Table 15.6 [38].

The fuel consumption depends on a number of parameters including average load, number of speed variations, chosen route, wind and rain, waves, degradation of the hull and drag of the ship.

15.5.2 Average Auxiliary Engines

All ships use residual fuel and need it to power different engines and equipment on-board. When the ship is at sea, the heat is taken from the exhaust gas through the steam boilers and hence no additional fuel is consumed. In port, the main engine does not run and the ships need auxiliary engines and boilers using extra fuel to generate heat.

The SFC of auxiliary engines primarily depends on the power they need; see Table 15.7 [39].

The average calculation of a ship's economy includes the auxiliary engine's fuel consumption although the load and operating hours of auxiliary engines greatly varies between types of ships. This is especially true in tankers, where heat is required for cargo heating, pumping, and the energy supply of auxiliary equipment. Fuel consumption of auxiliary equipment in tankers can be 20–25% of the whole consumption.

Type of ship Gross
tonnage
DWT		 Voyage
per annum		 Load Discharge Weight of
boiler fuel
t (lb)
Very Large Crude Carrier
Tanker and greater		 200,000 10 5 5 250
(550,661)
Suez Max Tanker 120,000–199,999 12 6 6 150
(330,396)
Aframaxa Tanker 80,000–119,999 – – – 60
(132,159)
Small Crude Tankerb 60,000 – – – 30 (66,079)
10 (22,026)
5 (11,013)
Product Tankerc – 50/60d
(110,132/
132,300)

Table 15.8 Boiler's fuel consumption for auxiliary equipment on tankers

Table 15.8 shows the boiler fuel consumption for auxiliary equipment in tankers [40].

Air-conditioning requires a performance of approximately 5.0–10.0 W (6.8– 13.6) 9 10-3 HP per 1.00 kW (1.36 HP) of the main engine power on an average merchant vessel. With the increase in average air temperature because of climate change, also the costs of air-conditioning and perishable goods' cooling in shipping will increase [41].

15.6 Recycling and Climate Balance of Transportation

Recycling has a growing meaning in environmental technology. Today, an increasing number of people want vehicles, airplanes and ships which meet the highest environmental standards, including recycling. People require batteries which do not have heavy metals, coolants which are biologically degradable, construction which can be recycled and energy recovery systems which use the stored braking energy.

15.6.1 Recycling of Vehicles

In accordance with legislation, all parts of road vehicles, airplanes, and ships have to be recyclable by up to 90–95%. Besides traditional materials for building

a Heated cargo 50 days per year b Heated cargo 100 days per year c Heated cargo 150 days per year d 40% of oil fuel is used for heating charges

Fig. 15.7 Recycling and climate balance

vehicles, such as steel and aluminum, light plastics, composite, and fiber glass strengthened materials are increasingly used and recycling them requires a specific technology; see Fig. 15.7 [42].

Light construction plastic materials on average require a higher level of energy in the production process than considerable metal products. That is the reason why plastic elements of road vehicles, airplanes, and ships are usually difficult to recycling and need a very long time to decomposing. There are still a lot of open questions for future development in production and recycling of light construction materials.

15.6.2 Recycling of Airplanes

As airplanes are very expensive, most of them are typically leased for 20–40 years. Very few go back into service after a long lease because evolving aerospace technology leaves older airplanes unable to compete against newer airplanes, which can be operated at a lower cost with decreased fuel consumption.

To protect the environment, professional decommissioning and recycling of older aircraft will increase in the future. There are no regulations for recycling airplanes. Many of them stay in the desert. Expensive equipment for aircraft, e.g., navigation and safety devices are often collected and utilized in special second uses [43].

The self-obligation of aviation companies is moving in the right direction. Many of them wanted to realize 50% recycling or more. In the future, legislation should be similar to cars and 90–95% of all parts of an airplane should be recycled.

15.6.3 Recycling of Ships

An agreement for safe and environmentally friendly recycling of ships has a lot of unanswered questions. Ships from member states will only be allowed to be scrapped if basic environmental and climate protection rules are in force. Currently, there are only some countries which have specialized reglementations in cutting up ships. Similar to aviation, the environment and ecology need common legislation for the recycling of ships.

Steel plays an important role in maritime shipping. Steel is the most important construction material and it is particularly close to nature. No other material has such a closed circuit and can be recycled so often without losing its quality. In the long run, the demand for new steel types remains high. Annual steel consumption will probably increase by 40% within the next 10 years. This tendency will determine recycling technology in future ships [44].

15.7 Summary and Recommendations: Climate Protection in Transportation

The amount of CO2 emitted from all means of transportation depends on the type of fuel. Certain fossil fuels contain more carbon per energy output than biogenic and synthetic fuels and hence produce more CO2 emissions per unit of work done.

Although future scenarios contain positive assumptions about biogenic and synthetic fuel use, the market penetration of individual fuels shows the leading role of fossil fuels between 2020 and 2050:

  • Petroleum or gasoline will remain the most important energy source supplying from 16 to 28% of the world's primary energy demand; and
  • Mineral oil and natural gas products as fuels will contribute to the transportation from 57 to 82%.

The Kyoto Protocol, Annex I, Article 2.2 made requirements for the reduction of the emissions of climate gases in 1997. Members of the United Nations Framework Convention on Climate Change (UNFCCC), a sub-group of the UN, take the necessary actions in two ways:

  • Controlling emissions in national regulations. The precise accounting of fuel consumption is a good indicator of the real activity; and
  • Setting targets for all sectors of transportation and developing global and regional policies within a limited time according to the UNFCCC review.

15.7.1 Vehicle Technology

Road transportation emits approximately 3,500 9 106 t i.e., 7,717 9 109 lb CO2 in the atmosphere yearly. This is approximately 0.2% of the absolute CO2 content of the atmosphere.

The pace of change in road transportation strongly depends on the price of oil. Vehicles emit the highest amount of GHGs such carbon dioxide and other substances, which negatively influence the climate and the environment.

Besides regulations, the following measures can effectively reduce fuel consumption and emissions:

  • Widespread use of sensor, actuator and computer technology, data communication, stream lining, heat insulation, engine efficiency, light weight construction, etc.;
  • Increasing driving efficiency with improved navigation;
  • Financially right and socially well-balanced introduction of climate protection measures, e.g., taxes;
  • Reducing the transport demands between work and residences;
  • Reorganization of districts for work, residence, and recreation in cities;
  • Improvement of conditions in mass transportation; and
  • Decreasing the costs of public transportation.

Changing the awareness of people depends more on motivation than on technology. Programs can teach drivers to save fuel and protect the climate.

15.7.2 Aviation Technology

Trends of gas and noise emissions in commercial aviation show that CO2 emissions will rise from the recent level of 733 9 106 t i.e., 1,615 9 109 lb to 1,480 9 106 t i.e., 3,264 9 109 lb by 2025. NO and NO2 mass is expected to grow from 2.5 9 106 t i.e., 5.513 9 109 lb in 2000 to 6.1 9 106 t i.e., 13.40 9 109 lb by 2025.

Aviation intensively influences the climate because jet airplanes fly at high altitudes near the tropopause and emit particles and gases, and leave contrails. Both can increase cirrus cloud formation. Airplanes can also release chemicals that interact with GHGs in the atmosphere. Nitrogen compounds are particularly dangerous, because they destroy ozone molecules at high altitudes.

Emissions from passenger aircraft vary per passenger kilometer, according to the size of the aircraft, the number of passengers on-board, and the cruising altitude. The rule of thumb shows that the average level of emissions depends on the distance of the flight:

• Short-haul airplanes on flights under 463 km (288 mi) or under 3 h emit approximately 259 g km-1 of CO2 (9.1 oz km-1 or 14.71 oz mi-1 );

  • • Mid-haul airplanes on flights over 463 km (288 mi) up to 3,000 km (1,863 mi) or between 3 and 6 h emit 178 g km-1 of CO2 (6.28 oz km-1 or 10.1 oz mi-1 ); and
  • Long-haul airplanes on flight over approximately 3,000 km (1,863 mi) or more than 6.5 h emit 114 g km-1 CO2 (4.02 oz km-1 or 6.47 oz mi-1 ).

The SFC per passenger and kilometers in aviation is approximately 130–140 g (4.59–4.94 oz) and similar to the emissions of a car with four seats and one person on-board. New developments may produce emissions lower than 100 g (passenger km)-1 , i.e., 5.68 oz (passenger mi)-1 for very large jet airliners.

Currently, the taxiing noise level of most Western aircraft is between 123 db(A) and 133 db(A). Specific noise level of airplanes is decreasing in course of new technologies in aviation. However, the average noise emission level near terminals of airports will increase from 24 dB(A) in 2000 to 30.3 dB(A) by 2025 due to the higher air traffic.

15.7.3 Maritime Technology

Currently, ships emit less than 1,000 9 106 t i.e., 2,205 9 109 lb of CO2 each year. Emissions have grown more than 85% since 1990, the base year of the Kyoto Protocol. Predictions show that global fuel consumption and CO2 emissions of ships will increase continuously and will be 160–284% higher in 2050 than in 2009. However, new technologies can decrease ships' fuel consumption and emissions.

Short-term goals are slow steaming and optimal use of existing technologies and resources. Long-term goals require new technologies, particularly the use of renewable energy sources in ships. These measures require not only new technology but also new international and national laws. Scenarios predict an increase in maritime emissions of 75% by 2020. The reason is the expected growth of the world trade fleet, which cannot be balanced with improved SFC of new vessels.

UNFCCC has the goal to reduce emissions from ships by 40% by 2020 and by 80% by 2050. New propulsion systems are needed, which could reduce emissions from ships by 10% and improved operations, which could reduce them by another 10%.

References

References 243

  1. Environment Statistics: CO2 Emissions by country. http://www.nationmaster.com/graph/ env\_co2\_emi-environment-co2-emissions

Chapter 16 Transportation Costs

Developments in transportation intensify effectivity of individual sectors of the economy. Beside freight transport, transportation has a high impact on labor mobility which is directly embedded in economic conditions not only in the private but also in the enterprising sphere. On the other side, economic development depends on engineering sciences, because technology forms the frame conditions of global transportation.

16.1 Tendencies of Fuel Supply

The transportation especially strictly depends on production conditions of the oil industry. Strategy in fuel production has to be considered in transportation planning [1]. Since 1980, the discrepancy between oil production and new discoveries has increased (see Fig. 16.1).

The linear extrapolation of the recent fuel consumption of approximately 4,700 9 106 t i.e., 10,362 9 109 lb per year predicts an increase to approximately 5,000 9 106 –6,000 9 106 t i.e., 11,023 9 109 –13,228 9 109 lb per year in world oil consumption in the next years. This tendency should lead to the consumption of the half of all oil reserves on the Earth by 2030. The total CO2 emissions would probably grow from the current level of 14,000 9 106 –16,000 9 106 t i.e., 30,867 9 109 –35,276 9 109 CO2 per year to approximately 25,000 9 106 – 30,000 9 106 t i.e., 55,119 9 109 –66,143 9 109 lb per year in 2030 [2].

16.2 Prices of Fuels

The costs of fuels are very unevenly distributed on the Earth (see Fig. 16.2). Unbraked development would require lower fossil fuel prices on the world [3]. Apart from single processes, the global growing tendencies in fuel price level are

Fig. 16.1 Discrepancy between oil production and new discoveries

Fig. 16.2 Price of petrol in 2010

very similar. The example of Germany shows the typical changes in the price of fuel in the last decades (see Fig. 16.3).

An acceptable petrol reduction can be achieved by using pure biogenic fuels of the first generation, such as alcohols and FAME, but at a substantially higher cost level than consuming conventional fuels (see Fig. 16.4) [4].

Second-generation biogenic fuels promise to be cheaper but the technology is still under development and only a few countries such as Brazil use them. The amount of fuel that can be produced is limited by the amount of crops that can be grown.

Biogenic fuels can be produced at lower prices in the future. In the long term, the most economic solution is the production of BTL, but it requires new innovations and a high level of research. On the other side, excessive use of biogenic fuels could endanger the world's agricultural areas because of the increasing use of pesticides and artificial fertilizers on industrial produced monocultures.

Fig. 16.3 Tendencies of fuel prices in Germany

Fig. 16.4 Retail costs of fuels in 2010

16.3 Prices of Measurement Technology

Scientific measuring instruments for analyzing engine's emissions which are needed for development and Type approval in transportation, cost more than €100,000–150,000 or US \$143,000–214,500 at the same level [5]. Laser remote sensing, depending on the type, costs on average between €50,000 and 100,000 or US \$71,500 and 143,000 [6].

The measurement devices for Type approval are the same for vehicles, airplanes, and ships:

  • Chemo Luminescence Detector for NOx, i.e., the sum of NO and NO2;
  • Flame Ionization Detector for HC; and
  • Fourier Transformation Infra Red device for CO and CO2.

Sensors for temperature, pressure, and oxygen concentrations in exhaust gas cost only one to two dozen Euros or US Dollars, because mass production lowers their cost. It is expected that the development of selective and durable OBM sensors for the measurement of exhaust gases is more expensive and the process requires a longer time interval.

| Category | Parameter | | | | |------------------|--------------|-------------|-------------------|--| | | Size | Performance | Price | | | | l | kW | € | | | | (in3
) | (HP) | (US \$) | | | Low classa | \1.4 | 80–110 | 15,000–16,000 | | | | (\85.4) | (109–150) | (21,450–22,880) | | | Mid class | 1.4–3.6 | 110–130 | 23,000–27,000 | | | | (85.4–219.7) | (150–180) | (32,890–38,610) | | | Upper classb | [3.6 | 220 | 70,000–76,000 | | | | ([219.7) | (299) | (100,100–108,680) | | | Hybridc | 1.5 | 84 | 22,000–27,000 | | | | (91.5) | (114) | (31,460–38,610) | | | Gas powered card | 1.4–3.6 | 96–111 | 20,000–25,000 | | | | (85.4–219.7) | (131–151) | (28,600–35,750) | | | Electric car | | | | | | Mid classe | | 147–221g | 80,000–90,000 | | | | | (200–301) | (114,000–128,000) | | | Top classf | | 240–250h | 200,000–220,000 | | | | | (326–340) | (286,000–314,000) | |

Table 16.1 Technical parameters and list price of cars

16.4 Costs in Road Mobility

When automobiles were first produced they had large engines with low rpm and heavy construction with long durability and an extremely high price. Later mass production led to low prices of cars and all social classes could buy them. In 1957, a Fiat Nouva 500 cost DM 2,650, in 1970 a 500 Luxus cost DM 3,850, and currently the new Fiat 500 costs €11,300 [7].

The price situation of cars, depending on size, performance, and special equipment is presented in Table 16.1 [8].

Electric cars will only sell after the battery price drops to about €5,000, i.e., US \$7,150. Some manufacturers are planning to rent rather than sell future electric cars or the battery to avoid the high cost of purchasing one [9].

The cost of automobile transportation, particularly fuel cost, will generally increase in the future (see Fig. 16.5).

a Convertible with special equipment costs €20,000–25,000, i.e., US \$28,600–35,750 b V6 design of engine

c Electric motor performance 10 kW (13.6 HP)

d Maximum range 350–380 km (217.5–236.2 mi), reserve gasoline tank's volume 12–14 l (2.64– 3.07 gal (UK) or 3.17–3.70 gal (US)), range 150 km (93.15 mi), top speed with high turbo

charging 200 km h-1 (124.3 mi h-1 ) e Acceleration from 0 to 100 km h-1 (from 0 to 62.15 mi h-1 ) in 4 s. The lithium–ion battery costs €15,000–20,000, i.e., US \$21,450–28,600 f Outside temperature of 20C (68F)

g, h Specific experimental models

Fig. 16.5 Predictions of road mobility prices

16.4.1 Improvements in Low-Cost Car Models

Small, cheap, and fuel-efficient vehicles are advancing fast. Low-cost models have become a new market segment. The upper financial limit of purchase depends on personal incomes in each region [10].

Retrofitting fossil fuel engines with natural gas combustion adds on average €280–300, i.e., US \$300–329 to the list price of a car with a spark ignition engine and adds €680–900, i.e. US \$972–1,287 to the list price of a car with a diesel engine. Higher purchase prices usually amortize after 2–4 years. The surcharge depends on the price of fossil and gas fuel [11].

16.4.2 Safety and Health

Vehicles influence health by noise, exhaust gas and particle emissions, and accidents. However, the risk of traffic accidents is usually lower than the risk of an accident in the home.

In highly developed countries, traffic is increasing while fatal accidents are decreasing. In developing countries, most accidents are caused by poor planning, inadequate design, old infrastructure, and lack of driver training. Efficient emergency services are needed to reduce the severity of accidents [12].

WHO estimates that approximately 1.3 million people are killed and more than 50 million people are injured in accidents each year. Transportation safety is very problematic in some developing countries with more than seven fatalities per 1,00 thousand million km, i.e., 4.35 fatalities per thousand million mi. Countries which

Fig. 16.6 Current and predicted traffic fatalities in the world

have the best infrastructure, present the highest safety on roads with 3.5 fatalities per thousand million km, i.e., 2.17 fatalities per thousand million mi (see Fig. 16.6).

Lead emissions have been successfully reduced. Calculations show a positive trend, thanks to the increasing introduction of lead-free fuels. The forecast is less favorable for other pollutants because the total number of cars is increasing and emission controls which are technically possible have not been universally adopted. Outside Europe and Japan, people do not treat noise as a health risk despite the increasing standard of living.

One of possible ways is the increasing intelligency of road vehicles. Selfdiagnosis provides visible results on-board. Visualization of dynamic driving character in driving schools can contribute to an improvement in driving behavior and to a long-term improvement in traffic safety.

16.4.3 Environment and Climate Protection

Reducing fuel consumption limits climate change. Efficient cars are important for saving energy. They can reduce the dependence on oil imports and its associated geopolitical risks [13].

The estimation of the speed of climate change over time is the biggest unsolved problem of climate predictions. Newest environmental conceptions require CO2 limits for new cars at 120 g km-1 , i.e., 4.23 oz km-1 or 6.81 oz mi-1 by 2012, 80 g km-1 , i.e., 2.82 oz km-1 or 4.54 oz mi-1 by 2020 and 60 g km-1 , i.e., 2.12 oz km-1 or 3.408 oz mi-1 by 2025. Further requirements are penalties of €150, i.e., US \$214.5 for each surplus 1 g km-1 , i.e., 35.3 9 10-3 oz km-1 or 56.8 9 10-3 oz mi-1 for additional CO2 emissions, with no exceptions for small-volume car manufacturers and no credits or incentives for cars that can run only on mixtures of fossil and biogenic fuels, or CNG or LPG without absolute decreasing SFC [14].

16.5 Costs in Aviation

Airplane operating costs are a crucial sales argument for the airlines besides safety, comfort, and environmental friendliness. This economic calculation includes direct, indirect, and total operating costs.

16.5.1 Development Phases

Modern airliners are designed for a life span of approximately 20 years and 60,000 Flight Cycles, i.e., landings [15].

The sequence of development of airplanes can be divided into phases of research and construction, preparation, and mass production.

These main stages have several smaller phases, e.g., technical preproject to define concept, building a prototype, carrying out a wind tunnel test, defining the preconstruction, working out of details of construction and of production documents, constructing mock ups, system trials, structural test plans, realizing flight tests for production, customized changes, technical improvements, and further developments (see Fig. 16.7).

Airplanes are produced according to their production documents and manufacturing processes. Mass production comes after completion of the mock-up phase.

16.5.2 Purchase Price

At first, the purchase price depends on production, i.e., on labor and equipment costs; see Table 16.2.

Turboprop engine-driven short distance airplanes are very economic. The range is very broad, and reaches up to €270 million, i.e., US \$307 million. Table 16.3 shows the main technical data and price of modern airliners from the manufacturer Embraer [26].

16.5.3 Operating Costs

The Direct Operation Cost (DOC) is determined by the technical data of the airplane. DOC can be divided into fuel costs (28.4%), costs of cockpit, and cabin

personnel (19.8%), landing and navigation fees for the airport and air traffic control which correspond directly to the weight (15.6%), the maintenance costs of the aircraft (8.8%) and of the engine (2.7%), the amortization (16.7%), the financing costs (7.0%), and the insurance costs (1.0%). The last three parameters directly depend upon the airplane's price [28].

The DOC of a medium range, single-aisle airplane can be reduced up to 0.40% by a 1% reduction in the SFC, up to 0.30% by 1% reduction in drag, up to 0.20% by 1% reduction in weight, and up to 0.25% by 1% reduction in investigations during development and production [29].

Experience shows that reducing the cockpit crew from 3 to 2 men saved approximately 4% of the DOC. Further crew reductions are planned for freight transportation. In civil aviation, two pilots will continue to remain in the cockpit in the future.

Unmanned airplanes, so-called drones has become more important not only in the military but also in the civil aviation for research, economy and ecology.

All new technologies in aviation aim to decrease the direct operating costs. Using rebuilt or new jet engines with propfans is one of the best ways to decrease SFC. A propfan is a modified turbofan engine with the fan placed outside the engine nacelle and sitting on the same axle as the fan blades of a turbofan. It is also known as Ultra High Bypass engine which requires an open rotor jet engine with contra-rotating blades. The design is intended to offer the speed and the performance of a turbofan, with the fuel economy of a turboprop [30].

Table 16.2 Price list of airplanes

| Category | Parameter | | | |--------------------------------|----------------------------|----------------------------------|--| | | Type | Price
106 €
(106 US
\$) | | | Small turboprop airplanesa | Q 200–Q 400b | 9.1–18.9 (13.0–27.0) | | | Smaller middle range airplanec | Boeing 737-600 | 39.8 (56.9) | | | | Embraer 195/CS 100 | 41.7–52.4 (59.6–74.9) | | | | Sukhoi Superjet 100d | 17.5–18.1 (23–25) | | | Larger middle range airplane | Boeing 737-800 | 56.6 (80.8) | | | | Boeing 737-900ER | 60.0 (85.8) | | | | Irkut MS-21e | 24.5 (35.0) | | | VLA | A 380 | 262.4 (375.3)f | | | | Boeing 787-8 (Dreamliner)g | 109.8–116.8 (157–167) | | | | Boeing 787-3 | 105.9 (151.5) | | | | Boeing 787-9 | 152.4 (218) | | | Military transporterh | C-130J | 50–65 (71.5–92.9) | | | Military fighter | Sukhoi Su-30i | 24.5–28.0 (35–40) | | | | F-16j | 10.2–13.2 (14.6–18.8) | | | | Dassault Mirage 2000k | 16.1 (23.0) | |

A propfan delivers 35% better SFC than contemporary turbofans, but it is very noisy. Therefore, application requires further passive and active noise protection measures which must also be included in the cost calculation. Military transporters use propfans because of their low fuel consumption and high durability.

16.6 Costs in Shipping

A ship's prices depend on its complexity, i.e., on the propulsion, the engine, and the auxiliary equipment, etc. Technology increasingly defines the costs of ships, not only in the military but also in the civil shipping too (see Table 16.4).

a Bombardier [16] b Stretched version of Q 400 in preparation

c Distance of flight 4,000–5,000 km (2,160–2,670 nmi) [17] d Russian airplane, expected to be introduced in 2012. Length 26–29 m (85–95 ft), seating

capacity 78–103 [18] e Russian airplane, expected to be introduced in 2014. The seating capacity is 150–230, 15% structural weight efficiency advantages, 20% lower operating costs and 15% lower fuel consumption than the Airbus and Boeing aircraft in the same class, e.g., A320 [19] f Depending on installed equipment [20] g First whole composite airplane [21] h Twin-engine, two-seat i Russian fighter [22]

j Light weight, for all weather, multirole fighter, sold more than 4,000 pieces on the world, price

1998 [23] k Turbojet driven [24, 25]

Table 16.3 Technical parameters and list of prices of C Series of Embraer

Parameters C Series data
CS100/CS100 ER CS300/CS100 ER
XT equals
''Extra thrust''		 Embraer 195
standard/advanced
range
Passengers 100–125 120–145 106–122
Engine 2 Pratt & Whitney
PW1524G		 2 Pratt & Whitney
PW1524G		 2 GE aviation
CF34-10E
Takeoff thrust per engine
kN (pdl)		 93.4
(675,343)		 93.4 (675,343)
XT::
103.6 (7,50,725 pdl)		 82.21
(5,94,432)
Length m (ft) 34.8 (114.1) 38.0 (124.6) 38.65 (126.72)
Height m (ft) 11.5 (37.7) 11.5 (37.7) 10.55 (34.6)
Wing span m (ft) 35.1 (115.1) 35.1 (115.1) 28.72 (94.1)
Empty weight 33,340 35,154 28,950/28,850
kg (lb) (73,436) (77,431) (63,767/63,546)
Takeoff weight 54,749/57,969 59,557/63,095 45,800/45,000
kg (lb) (120,722/127,822) (131,183/138,975) (100,881/99,119)
Max. landing weight 49,895 54,431 45,800/45,000
kg (lbs) (109,901) (119,892) (100,881/99,119)
Max. payload 13,971 16,556 13,650
kg (lb) (30,773) (36,467) (30,067)
Takeoff distance 1,509 1,872/1,890 2,179
ISAa
, SLb
, MTOWc (m)
(ft)		 (4,947) (6,138/6,197)
XT: 1,661 (5,446)		 (7,144)
Landing distance 1,423 1,521 1,282
ISA, SL, MTOW m (ft) (4,666) (4,987) (4,203)
Max. cruising speed Mach 0.82 Mach 0.82 Mach 0.82
Max. cruising altitude m 12,497 12,497 12,495d
(ft) (40,973) (40,973) (40,967)
Max. range 4,074/5,463 4,074/5,463 4,077
km (nmi) (2,200/2,950) (2,200/2,950) (2,201)
List price €36.7 million
US \$52.4 million		 €36.4 million
US \$51.9 million		 €36.3 million
US \$41.7 million

About 40% of all merchant ships are bulk carriers. They range in size from single hold mini-bulker to large bulk ships with DWT 365,000 t (359,252 ltn, i.e., 804 9 106 lb) [44].

The most expensive parts of ships are the embedded electronic modules, especially in navy ships. Therefore, submarines and aircraft carriers are the most expensive ships on the world.

a ISA international standard atmosphere b SL sea level, i.e., under IFR when flight altitude is above 912 m (3,000 ft) c MTOW maximum takeoff weight [27] d Max. allowed altitude

16.6.1 Improved Efficiency

The costs of operation per kilometer depend on the utilization of the capacity of a ship. In public transportation, such as ferries, fuel consumption and emissions could be reduced if it were possible to cancel trips that were under capacity. This measure could increase flexibility of ship owners in planning routes but reduce passengers' convenience. In similar cases, airlines substitute smaller airplanes for larger ones [45].

16.6.2 Early Scrapping

New ships are more efficient than old vessels. The life cycle of ships is long. There are a lot of vessels, which consume more fuel and emit more pollutants and noise than newer types. Replacing old ships with new efficient models reduces fuel consumption and emissions. However, the early scrapping of ships is a very complex decision involving a variety of factors such as expected fuel prices, the market forecast, the liquidity of the shipping company, and the expected capital return [46].

16.6.3 Costs and Tendencies of Natural Gas Application as a Marine Fuel

According to SOLAS, products of natural gas or biogenic gases are not allowed to be used on ship as fuels because the flammability limit is below 608C (1408F). Applications with gases without a special permission are not allowed because special tanks are needed for liquified or compressed gas. Although LNG is currently a cheap energy source, the drawback is that it needs high energy amounts to be liquid and to be safely stored on-board in the ship. CNG needs twice the tank volume than LNG.

The main reasons are

  • The ship cannot travel far enough on one pressure-tank load; and
  • The supply infrastructure is not sufficient.

Therefore, the best possibility to start using gas would be on ferries or vessels with short voyages according to experiences in Norway. In inland shipping, the use of LNG will rapidly gain high importance because of less pollution [47].

On sea, the introduction of gases as fuel is much more difficult, because of the small energy density of gaseous fuels. Ships have to carry a large amount of CNG to save the required performance [48].

LPG is heavier and less flammable than methane and burns at higher temperatures than CNG and LNG. The specific density higher than air requires special safety measures on ships. Additionally, LPG is more expensive and available in smaller volumes than CNG and LNG [49].

Table 16.4 List price of ships

Category Parameter
DWT Price
t 106 (€)
(lb) 106 (US
\$)
Small general cargo shipa 5,000–10,000 10–20
((11,025–22,050) 9 103
)		 (14.3–28.6)
Large bulk carrierb 150,000–180,000 20–40
((330,750–396,900) 9 103
)		 (28.6–57.2)
Modern handy size bulk carrierc 80,000–100,000 30
((176,400–220,500) 9 103
)		 (42.9)
Container shipd 1,000 TEU–14,501 TEU 10–145
(7.0–102.4)
Small chemical and LPG tankere 11,000–15,000 20–125
((24,255–33,075) 9 103
)		 (28.6–179)
Compressed Natural Gas (LNG) carrierf 30,000–36,000 200
((66,150–79,380) 9 103
)		 (286)
Raw oil and chemical tankerg 250,000–300,000 80–100
((551,250–661,500) 9 103
)		 (114–143)
Small passenger shiph 10–20
(14.3–28.6)
Highest class of cruise shipsi 450–750
(644–1,073)
Navy distroyerj 14,564 2,308
((32,114) 9 103
)		 (3,300)
Submarinek 350–4,895
(500–7,000)
Aircraft carrierl 100,000 699–8,042
(220,462) and over (1,000–11,500)

a LOA 70–120 m (230–393 ft), beam 15–20 m (49.2–65.6 ft), draft 6–9 m (19.7–29.5 ft) [31] b LOA 250–280 m (820–918 ft), beam 35–45 m (115–148 ft), draft 15–18 m (49.2–59.0 ft) [32] c With double side bulk, LOA 120–130 m (393–426 ft), beam 15–20 m (49.2–65.6 ft), cost is

depending on equipment [33] d Very variable size from small container ship to Ultra Large Container Vessel (Emma Maersk)

[34] e LPG tanker, not only for propane and butane, but for chemicals, such as chlorine, ethylene,

methyl bromide, etc. [35] f GT 40,000–48,000 t (88.2 9 106 –105.8 9 106 lb), NT 10,000–15,000 t (22.1 9 106 – 33.1 9 106 lb), capacity 50,000–70,000 m3 (1,766 9 103 –2,472 9 103 ft3 ), engine power 6,000–8,000 kW (8,046–10,729 HP or 20.5 9 106 –27.3 9 106 BTU h-1 ) [36] g GT 130,000–160,000 t (286.3 9 106 –352.4 9 106 lb), LOA 250–330 m (820–1,082 ft),

breadth 50–60 m (164–197 ft), depth 25–30 m (82.0–98.4 ft), draft 15–21 m (49.2–68.9 ft) [37, 38] h At first in coastal navigation [39] i QM2 [40]

j Zumwalt class, in series 2013, LOA 180 m (590 ft), breadth 24.6 m (80.7 ft), draft 8.4 m (27.5 ft), propulsion 78,000 kW (105,000 HP or 266.2 9 106 BTU h-1 ), speed 30 kn (56 km h-1 or 35 mph) [41] k Costs are depending on country of production, type, and equipment [42] l Costs are depending on country of production, type, and equipment [43]

GTL and biogenic fuels are energy carriers of the future. The production process of GTL consumes 40% of the energy contained in GTL. Biogenic fuels can gain a role in in-city ferry routes or other short sea trades [50].

In the 70s and 80s, scientists expected, that hydrogen will gain a leading role in the economy and ecology. However, currently, the dominant technology is steam reforming or hydrocracking. Hydrolization, a specific way of electrolysis means only a small portion of H2 production. On the other side, hydrogen requires approximately six times the space of LNG. The fight and safe storage of H2 on ships is yet a not solved problem.

16.7 Cost Saving in Transportation

Fuel price has become the most decisive factor in transportation. Unleaded gasoline costs on average €1.469, i.e., US \$2.1 in the EU. The span ranges from €1.212/l up to €1.662/l. The price of diesel has been intensively increased last years. Recent price ranges between €1.205/l and €1.667/l. The average is €1.180/l [51].

LPG has a ca. 60–70% lower price level. It costs approximately €0.8/l. The span ranges from €0.578/l up to €1.229/l. CNG has the same specific price level than LPG when the heating value per m3 or cu ft is converted to liter [52].

16.7.1 Vehicle Technology

Road transportation consumed approximately (1,290–1,350) 9 106 t y-1 ((2,841.4–2,973.6) 9 109 lb y-1 ) of gasoline and (850–880) 9 106 t ((1,872– 1,938) 9 109 lb) diesel fuel in 2009–2010. Until recently, most cars used spark ignition engines which burn gasoline; however, currently an increasing number of cars are using self-ignition engines which burn diesel fuel [53].

There is a high potential for reduction in fuel consumption and emissions. Experience shows that a 10% reduction in weight, a 10% reduction in air resistance, and a 10% decrease in rolling resistance in a mid-sized car leads to about a 6, 3, and 2% reduction in fuel consumption and exhaust gas emissions.

16.7.2 Aviation Technology

World aviation Jet A fuel consumption is approximately (258–270) 9 106 t y-1 [(568.3–594.7) 9 109 lb y-1 ] and kerosene consumption is about (68–70) 9 106 t y-1 [(149.8–154.2) 9 109 lb y-1 ] according to the statistics from 2009 to 2010 [54].

Average passenger airplanes use approximately 4.5 l fuel (100 passenger-km)-1 or 1.2 MJ (passenger-km-1 ), i.e., 52.3 passenger-mpg (US) and 62.8 passenger-mpg (UK). The newest very large airliners consume\3.0 l (100 km and passenger)-1 of fuel, i.e., 78.4 passenger-mpg (US) and 94.1 passenger-mpg (UK) because they fly at higher altitudes, i.e., above 40,000 ft (12,200 m) than conventional jet airplanes.

Similar to vehicle technology, a 10% reduction in the weight of airplanes leads to about a 7.5% and a 10% reduction in air resistance leads to a 4–5% reduction of fuel consumption.

Aviation technology is moving toward the intensive decreasing fuel consumption and pollutions. However, changes in the combustion processes are part of the natural aging of jet engines. Measurement and storage of the data of combustion products can provide precise information about the burning quality and help to find the right balance between the individual combustion chambers of the airplane.

16.7.3 Ship Technology

Transportation by water for large quantities of non-perishable goods is much cheaper than road or air transportation. World sea and inland navigation consumed approximately (360–370) 9 106 t y-1 ((793.0–815.0) 9 109 lb y-1 ) of heavy marine fuel oils in 2009–2010, which are specially refined types of petroleum, also referred to as bunker fuels [55].

Considering the increasing price of HFO fuel (€1.73 or US \$2.471 per gallon, i.e., €0.457 or US \$0.653/l for end-users) in 2011, the financial advantages of 1– 2% fuel saving could amount to €1.37–2.74 thousand million or US \$1.96–3.92 thousand million per year [55].

16.8 Summary and Recommendations: Costs in Road Transport, Aviation, and Maritime Shipping

A ''life cycle'' is the time interval from the beginning of the development to the end of the service life of all transportation means. It is different for road vehicles, airplanes, and ships. Life cycle assessment considers the following time intervals:

  • Technology development, preliminary designation, and Type approval and Type certification of road vehicles takes 3–5 years, of aircraft and of ships 5–10 years;
  • Production run of road vehicles takes 10–15 years, of aircraft and ships 15–20; and
  • Operation of road vehicles takes 15–20 years, airplanes and ships 25–30 years.

The total cost of a ship, an airplane, and a road vehicle is influenced by a chain of investments and events during the whole life cycle. The costs of development, Type approval and certification procedures have to be compensated with incomes during they service life.

16.8.1 Costs in Road Transport

The cost of car travel is rapidly increasing worldwide because of the rising cost of fuels. To increase private mobility for all social classes, manufacturers have built more and more fuel-efficient cars in the last decade.

The cheapest new cars in the world cost about €2,000, i.e., US \$2,859. They are mainly accepted in developing countries.

The future belongs to new technologies and new models, but only large financial investments can support the introduction of new technology, such as electric cars and new energy storage systems. Combustion engines will dominate development and will have cost advantages for the next few decades. Electric transport will remain at a relatively high cost level, including development, production, and daily operation.

16.8.2 Costs in Aviation

The Total Operation Cost (TOC) in air transportation is the sum of the Direct Operating Cost (DOC) and the Indirect Operating Cost (IOC), which are usually in a 100:80 ratio.

The direct operating cost can be reduced up to 4% by using high bypass ratios in turbofan jet engines. Using propfan engines saves up to 5%: The construction of a new type airplane with traditional ''heavy'' materials saves up to 1%, a new type with ''light'' alloys up to 2%, and with plastic materials up to 4%. The best costs saving, up to 12% of DOC would be from using ''super light'' composite materials with nano tubes as filling in the construction and propfan jet engines in the propulsion system. Rebuilding older jet engines in relatively new airplanes with propfan technology can save up to 10%.

IOC is reservation, sales and advertising (34% of IOC), administration and training (14%), fuel (35%), and dispatching (17%).

New technologies in aviation are expensive. High wing ratio and smooth, light fuselage construction need new innovations, inventions, and high investment over a long time. These measures have been effectively increased lift and decreased drag of new airplanes, lower fuel consumption, and TOC in the last decades. However, for economic reasons, relatively simple optimizations are in the most cases more practical, that the total reconstruction of the aeroplane.

Relatively simple measures are

  • Improvement of the aerodynamics of older airplanes;
  • Use of winglets;
  • Application of new aerodynamically optimized painting on the surface;
  • Realize of weight reduction; and
  • Introduction of new interiors.

16.8.3 Costs in Maritime Shipping

The costs per ton or nautical mile are the lowest in maritime shipping. Larger ships have lower costs. That is why ships in both ocean and inland navigation are becoming larger.

The costs of ships similar to airplane's cost structure can be divided into TOC, DOC, and IOC. The TOC depends on type, construction, performance, and on inbuilt electronic equipment. Technical measures to decrease TOC usually improve the hydrodynamics and aerodynamics of ships in water and in the air and improve engine, propulsion, and construction. Effective inspection and maintenance generally save fuel and costs.

Port infrastructure and connection of ports to their hinterland with rail and road networks also influence shipping costs.

Considering developing fuel prices and CO2 taxes, fuel consumption and exhaust gas emissions must be lowered in the future. Improving maneuvering and approaching routes near harbors and reducing waiting times at harbors also increase economy.

Expected, that in the future, harbor fees will be partly based on exhaust gas emissions. Not only CO2 emitted by combustion, but also hydrocarbons belong to GHG. Optimal bunkering and refueling processes are also very important. Other climate protecting measures come from using shore power in harbors for energy and cooling. This is the ''green'' power source from land produced by electric utility companies instead of the ship's engines.

The problem is very similar to aviation. Airplanes must be supplied by GPU, a specific type of ''shore power'', at airports. In the future, shore power can be generated by renewable energy sources such as wind, solar, biomass, or geothermal energy, depending on the local geography and infrastructure. However, the price of renewable energy for this type of energy generation is still high. Common taxation and promotion of shore power technology produced by renewable energy is in development.

References

References 261

  1. Portable laser gas detection systems. http://www.austdynatech.com.au/pages/resources/lasergas-detection-systems.php

Chapter 17 Future Transportation Systems

Instead of a quick revolution, new technologies will slowly evolve in all sectors of transportation. However, customers worldwide need sustainable, high quality transport at a reasonable price [1].

Figure 17.1 shows the expectations regarding properties of new transportation systems.

Change in road transportation, aviation, and ship navigation requires a high investment, a long time interval, and well-coordinated research activities worldwide to turn to sustainability. There are several possible paths what will be analyzed in next paragraphs.

17.1 Future Trends of Road Vehicle Technology

Development of vehicle technology can be divided into:

  • Methods for short distance travel; and
  • Methods for long distance travel.

One supposes that people will use electric vehicles for short distance travel. Cost-based predictions show that internal combustion engines will retain their leading position in the near future for both short- and long-distance transport.

Although the price of petroleum products is rising worldwide, there will be an increasing number of single quality combustion engine cars especially in the lowand mid-size class; see Table 17.1 [2].

Fig. 17.1 Expectations regarding properties of new load vehicles

17.1.1 Near Future Phases of Development

It is predicted that new technologies will make it possible to decrease the prices of small cars to a reasonable level. Therefore cost-efficient and low performance four-seat family cars will be increasingly used in both highly developed and developing countries.

The trends indicate the largest growth rate to be in freight transportation in all industrial sectors. The number of commercial vehicles is expected to increase by about 55% in the next 20 years.

17.1.1.1 Combined Combustion System

Homogeneous and lean combustion is essential to further decreasing fuel consumption. The aim is to lower pollutant emissions in the engine not in the exhaust gas after treatment system because the use of an external system behind the engine can considerably increase the fuel consumption.

Homogeneous burning aids both the spark and the self ignition engine in two ways:

  • In the spark ignition engine the burning process is similar to the advanced self ignition engine which operates with lean and homogeneous fuel mixture in the combustion chamber. This technique is called Controlled Auto Ignition (CAI); and
  • In the self ignition engine the burning process is similar to the advanced spark ignition engine which operates with high pressure fuel injection and high exhaust gas recirculation rates. This technique is called Homogenously Charged Compression Ignition (HCCI) [3].

With CAI and HCCI technology, particle emissions should be almost completely eliminated. The NO and NO2 emissions can be decreased by up to 4% and fuel consumption by up to 5% compared to a traditional self ignition engine which uses a conventional high pressure injection. A disadvantage is the higher emission rate of CO and HC at lower loads. Improvements can be attained by improving the

Year 2020 2030 2040 2050
Number of cars 9 109
North America 0.34 0.39 0.41 0.43
European Union 0.27 0.29 0.32 0.35
European countries not in the EU 0.11 0.18 0.20 0.24
Japan 0.09 0.10 0.13 0.15
China 0.09 0.20 0.22 0.24
Other Asian countries 0.11 0.18 0.21 0.24
Other continents 0.19 0.24 0.27 0.29
Total 1.20 1.58 1.76 1.94

Table 17.1 Prediction for car numbers up to 2050

shape of the combustion chamber, controlling the combustion, optimizing the injection, and using a regulated exhaust gas recirculating system.

17.1.1.2 Downsizing the Engine

Downsizing the engine reduces the cubic capacity and the weight of the engine. However, the use of a very high number of revolutions can increase fuel consumption, especially in very small engines. Driving downsized engines in the best speed and gear ranges without excessive braking and accelerations saves a high amount of fuel and emissions [4].

It is possible to further downsize two- or three-cylinder engines with a Common Rail system which operate in all ranges of load at the most favorable number of revolutions especially in starting phases, which are highly sensitive against irregular running in small highly downsized engines. Electronic control will more and more support optimal operation in all ranges of number of revolutions and under all environmental conditions.

17.1.1.3 Turbocharging the Engine

Originally, the charging of piston engines was developed for aircraft engines to compensate for the reduced air density at higher altitudes and to compensate for the resulting reduction in the engine's performance. The turbocharger is a special device which forces more air and fuel into the engine. Unlike the compressor, which is driven by the crankshaft, the turbocharger is driven by the exhaust gas.

Variable Turbine Geometry makes it possible to regulate the charger pressure to a large degree. It is primarily used in self ignition engines due to the maximal exhaust gas temperature of 700–800C (1,292–1,472F).

The exhaust gas temperature of turbocharged spark ignition engines can reach a dangerously high temperature of 1,000C (1,832F) which is the usable limit of the advanced materials. These new materials make it possible to use high level of turbo charging as well in spark as in self ignition engines. Nowadays, for the

Fig. 17.2 Use of a positive displacement compressor in a four-cylinder spark ignition engine

required high temperature resistance in turbines constructors use nickel-based steel alloys [5].

Further devices are valves and pressure regulators for flexibly steering the charging air and the additional use of a compressor with an electric booster providing compressed air from the air reservoir.

17.1.1.4 Compressor Technology

Turbochargers can be started only when the engine produces sufficient exhaust gas. The turbo lag in the first seconds of start is an unfavorable side effect of this technology. Positive displacement compressors improve the engine response without significant delays or turbo lags. They need a direct drive, which is taken off at the crankshaft; see Fig. 17.2.

Positive displacement compressors usually run up to 2,000–2,400 rpm; the turbocharger starts at higher rpm. Future compressors will need high temperatureresistant materials, in the air intake as well, because they will operate with a higher number of revolutions and therefore at a higher charge air temperature. Monitoring emissions will become more important to achieve improved inspection and maintenance under extremely raw operation conditions [6].

Engine performance due to fully loaded and optimized compressor technology has increased by about 15% in the last years. However, the use of compressors also has disadvantages, such as the higher fuel consumption and the delayed start of the catalyst. The operation temperature of the exhaust gas after treatment system is higher compared to the turbocharged system and an early aging of the catalyst is possible.

The combined use of a turbocharger and a compressor needs less space than two turbochargers usually placed above the engine, because the turbocharger and the compressor can be put between the cylinder heads. This construction has a lower temperature in the engine compartment compared to two turbochargers. A lower temperature with better aerodynamics partly compensates for the higher fuel consumption.

Fig. 17.3 Common Rail and exhaust gas after treatment system in a self ignition engine

17.1.1.5 DPNR Technology

Injecting pure fuel into the exhaust gas when congestion in the particle filter is detected increases the temperature and leads to the combustion of the particles as well as to the reduction to nitrogen oxides. A system that includes exhaust recirculation is called Diesel Particulate Nitrogen Reduction (DPNR) which eliminates the remaining CO, HC, NO, and NO2 emissions in downstream catalysts. In this technology, no additional urea is necessary in contrast to the conventional SCR technique [7].

Today, a common exhaust gas after treatment system consists of:

  • SCR catalyst;
  • NOx storage catalyst;
  • DPNR catalyst;
  • Oxidation catalyst;
  • Particulate filter; and
  • Appropriate sensors; see Fig. 17.3.

17.1.1.6 Heat Recovery and Noise Reduction in the Exhaust Gas System

The primary task of the exhaust gas system is decreasing pollutant concentration in the exhaust gases.

The exhaust gas after treatment system of the engine discharges the exhaust gases and also recycles energy, depending on the engine power. Air-borne noise generated by the engine and from the exhaust gas system is harmful. The exhaust gas after treatment system must also reduce noise by means of mufflers [8].

There are three basic methods to improve the efficiency of exhaust gas after treatment systems:

  • Improving particle diminution in the engine's rough emission;
  • Combining the particle filter with the NOx reduction catalyst; and
  • Developing highly durable filters which can be frequently heated and regenerated.

This technology has been successfully developed over the last years, but still requires further investment, especially in heavy-duty vehicles and ships. In ships, the system can also recover heat, in order to use a part of the exhaust gas energy for preliminary fuel heating. An exhaust gas recovering system consists of a recuperator that may be a steam generator or a distribution heater fitted to the gas turbine or the self ignition ship engine.

17.1.2 Far Future Phases of Development

Although hybrid technology is state of the art in the spark ignition passenger car technology, the development will go more and more on in the self ignition and heavy-duty technology. Self ignition hybrid in passenger car is state of the art.

In the far future, electric vehicle technology could be improved in a way that is not yet imaginable. However, the rate of development is not sure. Recent experiences have proven that new technology will develop slowly and not in a revolutionary way. This includes the cost, safety, durability of the electric storage battery, the supplying manufacturers with new raw materials, e.g., with lithium and the recycling of all parts of the electric engine and the connected technology.

17.1.2.1 Hybrid Propulsion Systems

Hybrid technology means the common use of an internal combustion and usually an electric engine for driving. Theoretically, many principles are possible for hybrids, which can store and utilize the recuperated energy from braking, e.g., flywheel, hydrostatic systems, compressed air, etc., but today the electric solution seems to be the most viable way. Wide ranged applications for commercially usable vehicles with hybrid technology are available only up to lower mid-size performance. The main markets are Japan and the USA, but the European market is increasing [9].

There are new hybrid commercial vehicles in specific sectors of road transportation, e.g., in mining technology. However, the development is going in the direction of general using hybrid technology in road transport. In hybrid vehicles, recent performance of the internal combustion engine attaches 250–1,397 kW (335–1,873 HP), the cylinder volume reaches up to 7–16 l (0.25–0.56 ft3 ), and the

Fig. 17.4 Basic types of hybrid technology

electric engine has an average performance of 88.2–147.1 kW (119.9–200.1 HP), i.e., 10–15% of the internal combustion system excepted range extender technology [10].

engine

There are micro, mild, and full hybrid vehicles; see Fig. 17.4.

Hybrid cars are particularly advantageous in large cities, where traffic congestion causes an enormous waste of time and energy and where pollution causes several diseases and environmental damage [11].

Future hybrid motor vehicles will remain more expensive than similar cars with combustion engines, since all supplementing parts of the propulsion must be doubled, which measure increases the costs of production and maintenance. However, future vehicles with hybrid propulsion will be more comfortable and will need less fuel [12].

17.1.2.2 Electric Vehicles

The propulsion of an electric motor vehicle consists of the engine, the transmission system, and the power sensor which converts the accelerator pedal's position into the appropriate current and voltage regulator of the engine.

The main characteristics of electric vehicles depend on the battery type.

Any household electric socket can be used to charge the battery, supplying electric power of 3.7 kW (3.51 BTU s-1 ) per hour. Charging for one hour can fuel a trip of approximately 20 km (12.43 mi). Shorter charge times can be achieved by the use of an industrial current connection which is often used for forklifts in stores. It takes 100 times longer to recharge a battery than to refuel a combustion engine to travel the same distance [13].

The design of the newest lithium-ion batteries is compact, the construction is of a relatively light weight, and the durability covers approximately 10 years or 600,000 charging-discharging cycles. Some models are surrounded by a cooling gel and achieve 25–50% higher energy density than conventional nickel-metal hydrid batteries; see Fig. 17.5.

Lead–acid batteries are most common in road vehicles. In modern electric cars, nickel and lithium-ion technology are replacing lead–acid batteries.

The advantages of the lithium-ion technology are the high thermal stability and the high capacity. However, some elements have to be improved, such as the cooling unit, the battery management system, and the high voltage connection.

Batteries with organic lithium electrolytic solutions are combustible and can lead to severe injuries in case of accidents. Therefore, it is important to design future batteries that do not burn. For this reason, non-flammable lithium-polymer technology, including an electrolyte solution made of polydimethylsiloxane and electrodes designed with nanotubes will gain importance in the future [14].

Fiber-reinforced synthetic materials and metal containers with a strengthened wall are used to protect against mechanical shocks. The electronic control unit avoids overcharging the lithium-ion battery, saves it from damage when starting at high temperatures, and records events which are important for the maintenance of the system [15].

In contrast to the internal combustion engine, the electric propulsion must distinguish between short and long time engine power. The short time power is limited by the maximum power of the supply. The maximum power is a half hour

Fig. 17.5 Comparison of storage technology

of power which is limited by the permissible engine temperature. Depending on the kind of propulsion, the power factor is 1–2 min for short time and 30 min for long time. The maximum propulsion power must be monitored and reduced according to the limits of the power actuator, engine, and battery [16].

Table 17.2 shows the most important parameters of current electric motor vehicles.

An annual world production of 800,000 electric cars is forecast within 9– 10 years. In reality, experiences of the last years has proven that this prediction is highly uncertain; see Fig. 17.6.

In 25 years, the driving characteristics of electric cars could be similar to cars with self ignition engines. However, current electric cars are still slower and reach smaller distances than cars with internal combustion engines. Short distance transport of less than 20 km (12.42 mi) is most common in megacities and in congested areas. Here, nearly 80% of trips could be optionally made with electric vehicles.

Nowadays, there are first commercial vehicles with electric propulsion on the market. The GVW of current types is up to 12 t (26,432 lb). The performance reaches up to 120 kW (160.9 HP), the distance 200 km (124.3 mi) with one charging [17]. In the future, electric propelled commercial vehicles, e.g., buses can gain on importance, particularly in short range mass transport.

However, in the long distance transport, there are no real alternatives to the internal combustion engine in the next 20–30 years.

| Table 17.2 | Features of current electric motor vehicle | | | | | | | | |---------------------------------|--------------------------------------------|----------------------------|----------|-------------------------------|-------------------|-----------------------------------------------|--|--| | Type of motor
vehiclea | BTb | EEc
kW
(BTU s-1
) | ATd
s | MSe
km h-1
(mi h-1
) | ODf
km
(mi) | ECg kWh
(100 km)-1
(BTU (100 km-1
)) | | | | Car | Ni–Cd | 21
(19.9) | 9 | 90
(55.9) | 80
(49.7) | 18
(61.4 9 103
) | | | | Car | Ni–MH | 49
(46.4) | 7 | 130
(80.8) | 200
(124.3) | 26
(88.7 9 103
) | | | | Car | Lith.–ion | 62
(58.8) | 6 | 120
(74.6) | 200
(124.3) | 23
(78.5 9 103
) | | | | Commercial
motor
vehicles | Lead–acid | 80
(75.8) | 7 | 120
(74.6) | 90
(55.9) | 35
(11.9 9 103
) | | |

Fig. 17.6 Predictions for future propulsion systems

17.1.2.3 Electric Recharging Stations

Optimistic predictions say that by 2030 or 2050 no more new motor vehicles will be sold without electric or hybrid drive but in fact, the time when mass transportation with new technology can achieve a leading role at a reasonable price, seems to be very uncertain.

To supply electric cars a net of intelligent recharging stations will be necessary. The condition and the efficiency of the battery must be measured by the recharging stations. Future charging stations will be able to control the battery functions [18].

Pay stations at public parking places or at company parking lots will recharge most electric cars. The data will be passed on to a computer for accounting by the

a From 0 to 50 km h-1 , i.e., from 0 to 31.1 mi h-1

b BT battery type c EE engine efficiencies d AT acceleration time e MS max. speed f OD operation distance g EC energy consumption

Fig. 17.7 Connection of the electric grid to electric cars for charging and storing energy

energy supplier. The vehicle will be able to communicate with the on-board power supply system or its account data management at the recharging station.

17.1.2.4 The Electric Motor Vehicle as a Storage System

Renewable energy has the disadvantage of variable production which often does not meet the demands of industry or consumers. The power output of wind and solar power plants entirely depends on the weather; but energy consumption depends on the time of day. It would be ideal if electric cars could store and use renewable electric energy.

The additional power of wind or solar plants could be stored in the batteries of electric cars. This would improve the alternative network management and simplify the regulation of the net's stability; see Fig. 17.7 [19].

The timing of charging electric cars is very beneficial for the electric supply because motor vehicles should be recharged when the current is cheaper, i.e., at night. Workers would drive to work in the morning and while parked at their place of employment the extra current from the car could be fed back into the net at a top price.

Fig. 17.8 Required reduction of expenses in fuel cell technology

The electric car as a storage system is still a research project for the regulation and storage of electricity in a future grid, but it seems to be very meaningful.

17.1.2.5 Fuel Cell Technology

Fuel cells function similar to batteries and produce electricity from chemical reactions of H2 and O2 by combustion without flame at lower temperatures in the presence of catalysts. They replace large, heavy batteries, and run with a high efficiency and low emissions. Recent models are usable from a few Watts to a few Megawatts.

However, the price of fuel cell technology must be greatly decreased before it become popular; see Fig. 17.8 [20].

In solid oxide fuel cells, the temperature of operation decreases from 800C to 650C, i.e., from 1,472F to 1,202F. The technology uses a high power density and is of optimal durability. The oxide layer could be sprayed by an automated process which could be a path towards cost-effective mass production [21].

Solid Acid Fuel Cells operate at low temperatures, have a performance of 250 W (0.34 HP), and use diesel fuel for the hydrolysis. One predicts they are the best solution for the future [22].

Currently, there is no enough data on the life span and durability of fuel cells in regular use. The most important application of fuel cells is the production of energy in spacecraft and in submarines. This is still a very small field. Profitable mass production seems to only be realistic in the future.

17.1.2.6 Hydrogen in Fuel Cells

Hydrogen can be burned like gasoline inside the engine or used in fuel cells to generate power. A hydrogen fuel cell produces current made from hydrogen and station

vehicles

Well-to-wheels
Well-to-tank
(WTT, fuel chain)		 Tank-to-wheels
(TTW, vehicle)
Production Transportation Fuel processing Transport Distribution End use
Crude oil
drilling
and
pumping		 Crude oil
pipelines,
tankers,
trains, and
trucks		 Petroleum
refineries		 Gasoline
pipelines,
tankers,
and tanks		 Trucks and
refueling
stations		 Internal
combustion
engine
vehicles
Wind
energy		 Frequency
rectifiers		 H2
production
and storage		 Electric grids Connectors Electric
motor

Table 17.3 Full chain consideration of energy production for vehicles

systems

oxygen. Experimental electric cars with hydrogen fuel cells and electric motors produce 100 kW (94.79 BTU s-1 ) and have a range of 450 km (280 mi). The current is stored in a lithium-ion battery which powers an electric motor. A tank holds about 4 kg (8.31 lb) of compressed hydrogen [23].

Hydrogen has two main benefits. Its mass-specific energy content is three times higher than gasoline and it produces water in the exhaust of the combustion. However, production of pure hydrogen from water through hydrolysis requires high energy. Hydrogen produced from natural gas by hydrocracking is not an environmentally friendly production process.

Future generations of alternative energy will also improve hydrogen production, primarily through the use of wind power; see Table 17.3 [24].

The range of hydrogen-powered cars is further and the refueling time is shorter than of average battery powered electric cars. However, the storage of hydrogen is difficult and dangerous because its tiny molecules escape from almost every pressure vessel. These problems do not exist with liquid hydrogen. Hydrogen becomes liquid at minus 253C (-487F). This very low temperature is produced by cryogenization, which is an expensive energy-consuming process.

Hydrogen fuel cell technology needs a few more years of development until the cells are cheaper and convenient enough to be mass marketed. The attainable energy densities of electricity stored in batteries or of hydrogen stored in fuel cells cost about 0.01 kWh Euros-1 , i.e., 0.009 BTU s-1 Euros-1 . In comparison, the gasoline energy density costs approximately 6 kWh Euros-1 , i.e., 5.69 BTU s-1 Euros-1 [25], i.e., it is more economic.

According to experiences, it is not possible to replace fossil fuels such as gasoline, diesel, kerosene, or heavy marine diesel oil in the transportation of passengers and goods by known alternatives within the next decades. Alternative energy carriers and fuels will come slowly and replace fossil fuels only in a small sector of the market.

17.1.2.7 Natural Gas in Fuel Cells

CNG costs much less than gasoline or diesel fuel. The reason is not only its optimal physical and chemical properties, but also the current taxation system.

Vehicles powered with compressed or liquefied natural gas emit 25% less CO2 and 75% less pollutants than those using gasoline. Instead of natural gas, cars can use biomethane produced in a renewable way. Using Liquefied Petroleum Gas is usually less sustainable for the environment because it emits more pollutants in the exhaust gas [26].

Retrofitting costs €2,000–3,000, i.e., US \$2,860–4,290. Changing from gasoline to CNG to fuel a car is cheaper only after driving 50,000–70,000 km (31,075– 43,505 mi) per year. New CNG vehicles have a more reasonable price. In the future, the advantage of natural gas will certainly appear sooner for drivers because of the increasing price of gasoline and diesel fuels.

17.1.2.8 Methanol in Fuel Cells

The reformation of methanol (CH3OH) seems to be the key to fuel cell technology. Methanol is produced from natural gas with approximately 65% efficiency. It is a liquid similar to gasoline and diesel fuel, and has a high energy density. Methanol is available in the existing infrastructure.

The reaction takes place with air and water at temperatures of 800–900C (1,472–1,652F). Natural gas is partially oxidized and converted in two catalytic steps with H2O to H2, CO2, and CO. Carbonization and inhibition of the catalyst must be avoided. The remaining residue of CO must be separated by gas selection, because it inhibits the electrodes of the fuel cell [27].

The reformation of methanol is substantially more difficult than the conversion of methane to hydrogen. The process could be substantially improved in the future if catalytic technology were developed.

17.2 Future Trends in Aviation Technology

Civil air transportation will need approximately 24,000 new airplanes in the next 20 years. Freight transport is expected to increase 5.2%. About 3,440 new airplanes and approximately 850 rebuilt airplane will be needed for air freight service. The total cost of all the new airplanes will be approximately €145 thousand million, i.e., US \$210 thousand million in 20 years [28].

By 2030, passenger transportation will require approximately 1,700 Very Large Aircraft each carrying more than 400 passengers. The investments will cost €399 thousand million, i.e., US \$571 thousand million in 20 years.

There is a projected need for about 6,250 large airplanes carrying 250–400 passengers, i.e., 42% of the market and for about 17,000 small single aisle airplanes, i.e., 39% of the market in the same time interval.

17.2.1 Near Future Phases of Development

New technological innovations to reduce of fuel consumption will remain the focus of future airplane technology. Airplanes with large capacity and low operating costs will work more reliably and sustainably than current types. Future commercial aircraft will use highly advanced technology, but without spectacular innovations, similar to other types of transportation.

The design objectives in aviation are lighter structures, better aerodynamics, and new jet engines with lower fuel consumption, lower pollutant outputs, and GHG emissions and maximum safety.

17.2.1.1 Improved Aerodynamics

Reducing drag ensures the most benefits in fuel consumption and lowers operating costs. The improvement in the wing geometry of older models, compared to new types of airplanes could decrease aerodynamic resistance by approximately 12%. Variable wing profile in the rear area of the wing could also save 8–10% and will be advantageous especially when applying extended flaps. Improving aerodynamics is expected to save 3–4% of fuel while cruising despite the larger size and weight. The wing box would remain unchanged [29].

Winglets at the wing tip will be widely introduced and will already increase the aerodynamic efficiency of airplanes in the near future.

17.2.1.2 New Materials and Designs

Noticeable weight savings are expected through the use of better materials and improved designs. The best examples are aluminum–lithium alloys, which are 5% stronger and 10% lighter than conventional aluminum alloys [30].

In the future, Carbon Fiber Composite (CFC) will be extensively used in loadbearing structures such as the wings and the fuselage. Reducing weight with CFC will reduce fuel consumption by up to 25%. The rudder assembly was the first primary structure built with CFC material.

Today, CFC has already proven itself in secondary structures such as in spoilers and in landing gear. In the future both the quantity and the quality of new composite materials will increase. However, they will only become advantageous if their costs are reasonable, the inspection and the maintenance requirements do not increase, and the risks of using them are safely controlled.

17.2.1.3 New Fuels for Engines

Several airplane manufacturers are attempting to introduce new fuels for airplanes. Not only environmental and climate protection, but also the price of conventional fuel demands continuous development. New fuels based on sugarcane have been tested in several laboratories of the U.S. Air Force and the Royal Air Force. Manufacturers and legislators have predicted that biogenic fuels in aviation can be widely marketed [31].

17.2.1.4 Improved Propulsion Technology

The most spectacular step in the history of commercial flight was the transition from the piston engine to the gas turbine. There will not be similar revolutionary innovations in foreseeable future but a series of small improvements [32].

Greater bypass and higher compression ratios will further lower the fuel consumption. Enlargement will be limited by the increasing cross-section area and the higher aerodynamic resistance of larger jet engines with more and more increased bypass ratios. Currently, the upper limit seems to be a bypass relationship of approximately 10:1.

Future jet engines will work with even higher compressor pressure ratios which are over 50:1 but the turbine inlet temperature does not allow a ratio higher than about 45:1. If the ratio went above this then the maintenance costs would become too high. Emissions and fuel consumption can be decreased by 10% with improved combustion chambers. However, the technology will be developed slowly and research will become increasingly expensive.

New propfan engines will increasingly combine the advantages of turboprops and turbofans. The modified propeller drive of the fan will reach an efficiency of 80%. However, future improvements require better noise insulation of the fuselage. Passive methods such as optimal insulation walls and active sound reduction technologies, such as the use of fast regulated loudspeakers with different frequencies and amplitudes will gain a decisive role also in civil aviation. Currently, this technology is widely used in military transportation. Improvements in the construction of the transmission and in the design of the propeller blades can further decrease noise emissions and increase durability.

17.2.1.5 Fuel Cell-Driven Electric Motors for Taxiing

The use of advanced fuel cell technology could make taxiing near terminals more environmentally friendly. New type of electric motor could be built into the nose wheel of airplanes. Taxiing a mid-range single aisle airplane requires about 50 kW (67.1 HP) of energy with high torque [33].

The starting inertia of an airplane can be optimally overcome through the use of an electric engine in the first seconds of taxiing because they have relatively high performance with low inertia. A fuel cell can be installed in the fuselage near the wheel. The way to practical introduction of this technology is the development of light weight fuel cells with high efficiency because a large weight of current fuel cells could result in increased fuel consumption of the airplane in flight.

17.2.1.6 New Maneuver Control Concepts

Electronic flight management systems can improve maneuvering and compensate for vibrations by controlling the variable load on a wing by turbulence. Regulation can be done with high performance and high speed micro controllers, which allow fast redistribution of weight and changes in the wing profile according to the external aerodynamic conditions [34].

The distribution of lift forces along the wingspan of a commercial aircraft has an elliptical form. This distribution produces the lowest resistance while cruising. In maneuvers like turning along a curved trajectory, the wing must produce more lift. However, the distribution changes which leads to a higher load near the wing root. For this reason the wing must be strengthened for the increased load. This surplus weight must be carried unproductively while cruising [35].

Future control of maneuvering loads will be presumably able to make a fast redistribution of the lift forces, which depend on the angle of attack and altitude. By controlling the maneuvering loads, the lift will be shifted toward the wing root while the load on the outer wing will decrease.

Control of the maneuvering load will be managed by leading and trailing edge flaps, and spoilers. The wing profile will be varied by computer-based flight control systems. For cruising, the trailing flaps will be retracted. For landing and take-off they will be extended to increase the wing area and the camber.

The time span for regulation measures for flight maneuvers is extremely short. New, high speed and high capacity microcontroller systems will be increasingly used for this task.

17.2.2 Far Future Phases of Development

Airplanes which are just being tested in flight today will be in regular commercial service in the next 30–40 years. During their long service life, their interiors, fuselages, and cabins may be frequently modernized and their jet engines may be modified many times. Older airplanes can be retrofitted to the most modern standard. This is the way that airliners are going if they are rebuilt to being freight transporters after a long service time interval.

17.2.2.1 Construction of Large Airplanes

Airports and airspaces are currently becoming more and more overcrowded. Since air traffic will double within the next 15 years, the available airport capacities cannot handle these increases. Super large airplanes with 600–1,000 passengers could be a way out [36].

Future airports will manage large numbers of passengers, especially, if several large airplanes arrive or takeoff at short intervals. Airport services such as fire fighting, de-icing, and ground handling equipment will need to be increased. Future runways, taxi ways and aprons must be able to carry over 500 t (492 lnt, i.e., 1.102 9 106 lb), compared to 350 t (344 lnt, i.e., 0.771 9 106 lb) today. They will have to manage wing span widths of 85 m (278.7 ft), instead of 60–70 m (196.7–229.5 ft) currently, to keep parked airplanes from touching each other.

Will the fight for market share produce still bigger and faster airplanes? Airplanes will probably not be bigger or faster than the most recent large airplanes in the foreseeable future. In large airplanes, the design of the space for the passenger's compartment represents the greatest challenge, because more passengers must be accommodated in the cabin. Besides the fuselage, the wings and all other parts require new designs. The development is cost intensive and requires time.

17.2.2.2 Laminar Flow

Reducing air resistance permits flights at higher speeds and improvements in the glide ratio. In the last few decades, the average Mach number of civil aviation has increased from M 0.78 to M 0.82.

Adding winglets and improving the wing profile provides only a limited improvement. Apart from this technology, improving laminar flow will be a really revolutionary step. Currently, the boundary layer leads to friction resistance which is half of the complete resistance of a commercial aircraft while cruising. The Reynolds number determines whether the bordering layer will be laminar or turbulent. In flight there is a Reynolds number between 20 9 106 and 70 9 106 , so the boundary layer is always turbulent. With artificial laminar flow, the friction resistance could be reduced by 90%. No other measure yields such large benefits. This will be the central topic in future aeronautical research [37].

Improving the wing construction will produce laminar boundary layers. In practice, only a part of the wing will have a laminar flow, but with an artificial vacuum, 75% of the wing area will be attainable. At this way, friction resistance will be lowered to 30% and the glide ratio will be correspondingly improved. The profits will be considerable. 10% fuel will be saved on short range flights. Long range flights will save up to 20%. However, tests are still in progress.

17.2.2.3 Oversized Gliders

Wing load is the loaded weight of the aircraft divided by the area of the wing. The faster an aircraft is flying, the more lift is producing by each unit area of the wing, so a smaller wing can carry the same weight in level flight with a higher wing load. Correspondingly, the takeoff and landing speeds will be higher. High wing load also decreases maneuverability [38].

Table 17.4 shows the parameters of airplanes with different wing aspect ratios. The airplane of tomorrow can be constructed like an oversized glider with efficient aerodynamics, but the enormous wings will have to be reinforced through

Airplanes Velocity
km h-1 (mi
h-1
)		 Wing aspect ratio
[–]
Military fighter 1,800–2,700 (1,119–1,678) 4–6
Reconnaissance 900–1,200 (559–746) 4–6
Airliner 800–1,100 (497–684) 5–10
Transporter 600–700 (373–435) 7–10
STOLa 300–500 (186–311) 7–11
Sport airplane 100–300 (62.2–186) 4–9
Glider airplane 100–300 (62.2–186) 18–30

Table 17.4 Wing aspect ratio depending on flight velocity

strutting, to safely connect with the fuselage. If possible, the wings must be retractable to enhance the safety of taxiing; see Fig. 17.9.

Important aerodynamic improvements require further developments for attaching the fuselage to the wing. The tail unit and the horizontal stabilizers could be constructed with high vertical size. The optimally insulated engines with low noise emissions can be placed near the fuselage which can also stabilize the operation of the airplane [39].

The aspect ratio of the wing depends on the price of fuel. If the fuel is cheap, the price of the airplane is decisive and a very small wing aspect ratio is optimal. If the fuel is more expensive, small fuel savings are also profitable. In this case, manufacturers will build a larger wing aspect ratio which will be bigger than the optimal size.

17.2.2.4 Blended Wing Body Airplanes

Blended wing body airplanes could be introduced after 2050. Figure 17.10 shows a model of a blended wing airplane.

The cost of fuel will bring about a radical change in transportation. It is absolutely not certain whether a blended wing airplane will be developed, even in the distant future. An earlier introduction could be possible as an air freighter. However, from an operator's point of view, it is cheaper and simpler to convert a passenger airplane to being a freight carrier, after 10–15 years of service [40].

17.2.2.5 Electric Airplane Propulsion

Smaller experimental aircraft already use an electric powered propeller. The wing span is 13–14 m (42.6–45.9 ft), the empty weight with the battery is 250–300 kg (551–661 lb), and the motor produces 40 kW (54 HP) [41].

The battery supplies the engine with 66.6 V for a power of 30 Ah. The lithiumion-polymer battery provides 54 cells. The weight is 12 kg (26.4 lb) per cell, which

a Short takeoff and landing of airplane

Fig. 17.9 Large cargo airplane designed as an oversized glider

supplies power to the engine for 1.5–2.0 h. The price is about €100,000, i.e., US \$143,000.

The development of an all-electric airplane with fuel cell technology has high potential for saving fuel while cruising in the very far future.

17.2.2.6 Glider with Hydrogen Fuel Cell

The fuel cell powered experimental airplanes has two additional outer tanks under the wings for the hydrogen powered fuel Antares DLR-H2 cell and for the compressed gas. It is an unmanned airplane with hydrogen fuel cells which produces 25 kW (34 HP), i.e., 23.7 BTU s-1 [42].

The small airplane is able to fly 750 km (466 mi) in 5 h at a speed of 170 km h-1 (91.8 nmi h-1 ); see Fig. 17.11.

In the future, fuel cells may become more important in specific sectors of aviation, depending on their efficiency.

17.2.2.7 Solar Cell-Powered Airplane

Solar airplanes are equipped with solar cells. They are still able to fly around the world. The fuselage is 20–22 m (65.6–72.1 ft) long; the wing is 63.0–63.4 m

Fig. 17.10 Model of a blended wing airplane

(196.7–207.9 ft) wide on the leading edge. The airplane is built of CFC substances and honeycomb sandwich construction modules for the fuselage to achieve the required strength, rigidity and lightness. The wings have a lot of risks to strengthen the construction, e.g., 120 carbon fiber ribs at 0.5 m (1.64 ft, i.e., 0.55 yd) intervals to create the airfoil shape, and support the skin of the upper and lower wing. Therfore, the proportions of the experimental airplane and the length of the wing are very similar to a single-aisle airplane [43].

In fact, solar cells cannot provide the entire energy for future airplanes, but they can contribute to the utilization of solar energy as auxiliary power.

Fig. 17.11 Fuel cell powered experimental airplane

17.2.2.8 Development of Airports

All forecasts assume growth in air traffic. Particularly, the leading airports will have to cope with more air traffic in a few years. For solving the task, several ways are imaginable to increase airport capacity [44].

The first way is intensive international cooperation which will be generally necessary to solve the problems. In this process, airfreight may be shifted from civilian airports to former military airports. Parallel to it, smaller secondary airports could be strengthened more for intercontinental aviation with modern navigation and communication equipment.

The demand for very short distance air travel could decrease in the future depending on fuel prices, infrastructure, and economy. This problem should be solved by development of special low cost airplanes with open, contra rotating turbofan engines with high efficiency.

17.3 Future Trends in Ship Technology

Shipping will be presumably developed with the highest speed in transportation. However, development could be decelerated by intensively increasing fuel costs. In the future, ships will profitably use wind and sun energy. Theoretically, natural energy has an unlimited energy-saving potential on the open sea. Nevertheless, this attractive potential has not been used recently, because no existing photovoltaic, thermal, or solar power systems can fulfill all of the power requirements of a ship.

Fig. 17.12 Decreasing diesel nitrogen oxide emissions from ships

17.3.1 Near Future Phases of Development

New developments in all types of ships, such as bulk carriers, tankers, container ships, cruise ships or freighters, etc., will increase their safety, economy, power, durability, and flexibility. Besides the development with fossil fuels in the conventional way, continuous development will be possible if new types of fuels and renewable energy sources such as wind and sun energy will be used with higher efficiency. Complementary new propulsion technology will become more important.

Decreasing exhaust gas emissions with internal and external measures will be more important in the future. The inherent advantage of the slow speed marine diesel engine is its high efficiency. The amount of HC and CO in the engine's output is usually very small. However, the concentration of particles has to be decreased with a special exhaust gas after treatment system behind the engine, particularly when heavy fuel with high sulfur concentration is burnt. Marine exhaust gas after treatment technology is important for decreasing SOx, NOx, and particle emission concentrations.

17.3.1.1 Reduction of NOx Emissions

There are increasingly strict requirements for decreasing emissions from the engine and the exhaust gas after treatment device in marine technology. NOx emission values must be lowered to MARPOL 73/78 Convention, Annex VI limits between 2.0 and 3.5 g kWh-1 , i.e., 21.0 9 10-6 and 36.8 9 10-6 oz BTU-1 for ships launched after January 1st, 2011 [45]. A further stage is the 80% reduction of emissions with Tier 3 limits applicable from 2015/2016 [46].

NOx can be reduced by approximately 30–40% by injecting a direct water emulsion and through further measures, e.g., late injection; see Fig. 17.12.

Fig. 17.13 Changes in fuel consumption with fuel preparation and exhaust gas after treatment

The highest rates of reductions, of up to 95%, can be reached by the use of SCR technology. In a two-stroke marine diesel engine the SCR reactor nury advantageously be put in front of the exhaust gas turbocharger because of the optimal temperatures in the area [47].

Furthermore, there are several other methods for decreasing emissions. However, these methods usually have individual side effects which are disadvantageous. Humid air engines require less water, but need large humidification towers. Emulsified fuels require large quantities of water from freshwater production plants. Fuel-Water Emulsions (FWE) have lower heating values and higher viscosities than pure HFO. Emulsified fuels require an increased injection pump capacity and a bigger final heater [48].

FWE requires increased preheating temperature and higher feeder pump pressure to avoid water evaporation. Parallel to decreasing the exhaust gas emissions all these methods cause higher fuel consumption; see Fig. 17.13 [49].

Further aims for improvement of exhaust gas quality in marine technology are:

  • Reduction of NOx concentrations in the exhaust gas by 40–50% at sea and up to 80% in coastal waters, i.e., 50–200 nmi or 92.6–370.4 km off shore [50];
  • Reconstruction of existing engine technology on ships built before 2000 to be in compliance with the current NOx emission limits; and [51]
  • Lowering the operating costs and space requirements of exhaust gas after treatment systems for broad ranged applications [52].

17.3.1.2 Reduction of SOx Emissions

The average sulfur content of marine diesel fuel is 3.0–4.0% by weight. Operation with a standard HFO with sulfur content higher than 1% may lead to clogging the catalyst because the exhaust gas temperature of marine diesel engines is too low to avoid deposits under most operating conditions. The best results can be reached through the combined use of low sulfur fuel and SCR technology [53].

In the future, SOx emissions can be decreased by:

  • Global reduction of sulphur content of up to 1.0% by 2015. EU ports have required low sulphur content fuel since January 1st, 2010;
  • Global reduction of sulphur to 0.5% from 2020; and
  • General use of sea water scrubbers.

A special problem of ship technology is the demand for storage of the caustic soda produced on ships with the SCR technology through the use of sulfur-containing fuels.

A further problem of fuel supply is the cost saving bunkering of future, i.e., alternative fuels, such as synthetic and biogenic fuels, which need additional measures to be optimally bunkered. Alternative fuels and fossil fuels, such as HFO, MDO, and MGO require separated tanks and sensors to monitor combustion quality. Blended fuel requires homogenizers.

17.3.1.3 Reduction of Particles

Decreasing particle emissions is especially important in marine engines in comparison to other types of transportation. However, elemental carbon, such as soot, is by far the smallest part of particles emitted by marine diesel engines. Approximately 80% of the particles are sulfur products, such as sulfates and sulfur contained ash which are produced in the combustion process by sulfur in the fuel. The chemical process of sulfur reaction cannot be effectively influenced by the engine [54].

MGO fuel produces the smallest environmental problems burnt in ship engines. Typically, particle emissions from ships using MGO fuel are 30% lower than those using HFO fuel. The best levels of particle emissions can be reached in large, slow speed marine diesel engines. The concentration level of emissions in this case is comparable to high speed engines in automobiles.

The consumption of lubrication oil also contributes to the particle emissions. The amount becomes higher at high loads and high speed of the engine. Large marine engines usually do not need to change their lubrication oil [55].

IMO requires the reduction of particles in engines operating with HFO. Regulation of the sulfur content of fuel is only the first stage. Further important measures for lowering particle emissions are:

  • Improving the injection and nozzle system, e.g., introduction of slide valves;
  • Optimizing the mixing technology in the combustion chamber;
  • Using intelligent catalysts, particle filters, and scrubbers; and
  • Developing an entirely electronically controlled engine system.

17.3.1.4 Integrated Catalyst and Filter System

Currently, single filter system is state of the art in ship technology. In the long term, particle filters will be integrated into catalyst system in an effort to

Fig. 17.14 Common air intake and exhaust gas after treatment system

effectively reduce common NO, NO2, and particle emissions. Systems must be suitable for both retrofitting and for new engines. The required separation rate is approximately 70% [56].

Figure 17.14 shows the elements of the common air intake and exhaust gas after treatment system.

SCR and connected filter technology offers the largest future potential for the improvement of the exhaust gas treatment on ships. This procedure can be combined with exhaust gas recirculating and the catalyst can be integrated into the muffler. SCR technology in ships can only be used when ships combust low sulfur bunker fuels.

Filter on ships have to operate under raw conditions. The pressure difference in the filter between the entrance and the exhaust side can be measured with pressure sensors. A blocked filter leads to an increased pressure difference between the sensors. The filter must be regenerated before high counter pressure can seriously increase fuel consumption or stop the engine. In ships, the filter is heated by a burner to 600C (1,112F). Starting at 550C (1,022F), the deposited soot burns away and leaves the filter as CO2. If the filter is frequently clogged with ash, the regeneration requires longer time interval or higher temperatures. In critical cases, it cannot be regenerated anymore [57].

17.3.2 Far Future Phases of Development

17.3.2.1 Use of Biogenic and Synthetic Fuels in Ships

Future development will need cooperation between refineries and manufacturers of combustion engines. New generations of biogenic and synthetic fuels could be added to recent navy fuels in ratios of up to 20–25%. Liquid biogenic and synthetic fuels do not need a new distribution system and can be bunkered, and used in the existing fuel system.

However, new regulations are in the starting phase. Although CNG is a new fuel in road vehicles, with clear environmental advantages in comparison to oil products, CNG has been forbidden as a marine fuel by the IMO in international sea-going shipping for safety reasons up to now. According to SOLAS, only fuels

Fig. 17.15 Use of wind energy with Sky Sail technology

with a flashpoint of over 60C (140F) may be used on ships. That is the reason why kerosene is also prohibited. So far exceptions to this rule are ships in inland navigation, e.g., ferries and seagoing LNG tankers which are allowed to use the burn-off gas in their internal combustion engines [58].

17.3.2.2 Sky Sails

Tow kites generate 2–3 times the energy per square meter compared to normal sails depending on their shape which is comparable to that of a paraglide [59]. The kite system consists of a simple main stunt kite for propulsion, made of a strong and weather-resistant textile and is able to fly at altitudes between 100 and 300 m (328 and 984 ft), where steady winds are predominant; see Fig. 17.15.

Tow kites decrease the operating costs of a ship between 10 and 34%, depending on the wind. With optimal winds, fuel consumption can be temporarily reduced by up to 50%.

In the future, nearly all bulk carriers, cruise ships, and trawlers may use tow kites which can be retrofitted. This means that approximately 10,000 ships could be retrofitted worldwide with a tow kite system.

17.3.2.3 Photovoltaic Cells on Ships

Currently a new experimental ship with a four man crew, such as a catamaran with a particularly low hydraulic resistance coefficient and light weight is already able

Fig. 17.16 Solar and wind energy supply for a ship

to successfully navigate around the world using photovoltaic cells [60]. The ship is 23 m (75.4 ft) long, 6.1 m (20 ft) high, and reaches a weight of 85 t (187 225 lbs). It is built from CFC and other light weight plastics, and can run with battery power for 66 h, and costs about €1.0 million, i.e., US \$1.43 million.

Large vessels such as bulk carriers are also experimenting with photovoltaic cell technology. By means of some examples, the solar panels are installed on the deck of a bulk carrier; see Fig. 17.16.

Initial tests show that solar cells generate 1.4% more energy at sea than on land because of higher radiation intensity. However, photovoltaic solar power provides approximately 1–3% of the on-board electricity of large tankers, when all the free places are covered by solar panels. From experience, current panels survive severe conditions in heavy storms with constant rain, lightning, and pounding from waves up to 4 m (13.1 ft) high.

The far future aim is to use solar and wind power to reduce fuel consumption and CO2 emissions by up to 50%. The newest photovoltaic cells have efficiency of more than 17.5%, but their durability and costs for the marine technique must be still improved. The same requirements are valid for other alternative energy sources. Despite all improvements, the current level of alternative technology can only save a small part of the energy that a ship needs [61].

17.3.2.4 Hydrogen Fuel Cells in Ships

Fuel cell propulsion has been developed for submarines of first, because they operate without ambient air for a long time. Fuel cell technology in civil ships would provide a lot of advantages such as better environmental protection, lower costs, and higher durability than conventional propulsion systems. Civil ships usually use small and in the most cases transportable 160 kW (215 HP) hydrogen fuel cells in 20 ft containers consisted of four separate modules by a performance of 4 9 40 kW (4 9 54 HP).

Experimental equipment consists of a battery and a tank for hydrogen, similar to airplanes. The power is 160 kW (215 HP). Recent prices were over €2 million, i.e., US \$2.86 million, but in the future the expected price will be decreased to €300,000, i.e., US \$429,000.

In the first instance reasonable prices are necessary because a comparable marine diesel engine merely costs between €60,000 and 70,000, i.e., US \$85,800 and 100,000. Therefore, the production offuel cells for ship transportation can only begin when the cost of fuel cell technology generally drops by a meaningful factor [62].

Fuel cells generating approximately 500 kW (670 HP) are needed to drive ferries and recreational boats. Except for tests and demonstrations, the first mass produced fuel cells will be used in ferries and they will not be used on other ships until 2020–2025. Expected that the first freighters may be powered by hydrogen fuel cells about in 2030. Experimental and special research ships will probably be powered by a battery which will be recharged by a hydrogen burning fuel cell onboard earlier [63].

17.4 Summary and Recommendations: Future Environment Friendly Transportation

Electric drive and fuel cells can only be realistically introduced in the market when their price is reasonable. In the future, reduction of fuel consumption and exhaust gas emissions will become increasingly important. The requirements will impact both, the direct costs, i.e., the production as well as the indirect costs, i.e., the operation costs.

However, customers will certainly not be willing to pay the higher costs, if the only benefit is the protection of the environment. More safety, higher intelligence, more comfort, better durability and lower specific costs are also decisively important.

17.4.1 Future Vehicle Technology

The internal combustion engine will not be replaced in the near future but rather will be continuously developed. In highly intelligent cars, navigation can effectively contribute to lower fuel consumption and emissions. Cars and trucks, driving in convoys could additionally save fuel and space on the highways and main traffic roads. The combined combustion of natural gas and petrol as a fuel will be further improved in the near future.

Future pollution can be reduced by about 30% by premixing the fresh air and the fuel, recirculating the exhaust gas, using a SCR catalyst, and a particle filter system. Passive filter systems consist of a single filter and a catalyst module, which filter up to 70% of the particles. In these simple filter systems, neither an electronic nor an engine control system needs to be adapted. In opposite to them, active filter systems are common with the catalyst, are connected to the ECU, and can be regenerated by heat when required. They reach a higher rate of filtering than passive filter systems, but their costs are higher.

Hybrid vehicles with both an electric motor and an internal combustion engine will become more accepted in certain regions, initially in megacities. Electric motors can be optimally used when large forces are needed, when accelerating, driving up hill, and in ''stop and go'' traveling. Nowadays not technology or human behavior, but traffic jams are usually the main reason for higher fuel consumption and higher exhaust gas emissions.

In the future more plug-in hybrid vehicles will be recharged from the net, extending their range. The cost of hybrid systems will remain very high, since a combined system must contain many duplicate elements in comparison to single systems. Due to new promising developments in low and high temperature membrane technology, many manufacturers consider the fuel cell as an alternative to the combustion engine. May be, future designs could sooner prefer fuel cells. However, the single cell is only one component of the combined engine and storage system in the vehicle. Realistically, it will be a long time before it is on the market.

Self Diagnosis system will ensure that internal combustion engines operate with optimal combustion and beyond it, at the best range of load level and number of revolutions over longer distances. The specific fuel consumption and the pollutant emissions of future cars will be lower, in comparison with recent types, particularly in urban traffic. The energy of future electric vehicles will be stored in new types of lithium-ion batteries.

17.4.2 Future Aviation Technology

The airplanes of the future will presumably look just like those of today. However, finances, not the engineering, will more and more determine future designs. The cost of the fuel, operation, inspection, and maintenance, as well as environmental friendliness will powerfully influence the economy of an airliner.

Biogenic and alternative fuels or other renewable energy sources will become more important to protect the environment and the climate. Other aspects will also become more important, such as the use of light weight materials, the introduction of laminar flow over the wings, the integration of airframe, and nacelle and new engine technologies.

Airspace near airports is overcrowded everywhere, so aviation must develop higher safety standards. The growth of aviation requires new innovations, such as

  • The Single Sky initiative in Europe, flights on individually optimized tracks and profiles, independently from the established route structures;

  • The complete digitalization and automatic communication between airplane to airplane, not only between pilot and flight officer;

  • • Last minute changes in infrastructure posing hazards to operation, e.g., weather advisories;

  • Introduction of free flying areas; and

  • New policies at airports.

In Europe, people have a great sensibility to noise. However, there are other regions in the world whose habitat do not have such high requirements for noise emissions. The further decrease of pollutant emissions and noise will raise costs, because positive results usually require a cost-intensive and long development phase. New turbofan and propfan engines will produce less noise in comparison with older propeller and turboprop or turbofan engines.

At the start of the twenty-first century, consolidation in the aviation industry has meant that only a few manufacturers have kept producing commercial passenger airplanes. However, tendencies are proving that new manufacturers in several countries will independently start producing modern airplanes in the next years and decades.

Can nuclear power replace oil? There were projects with nuclear-powered airplanes in the Soviet Union, the USA, and Great Britain at the beginning of the 1950s. The hopes of these projects could not be achieved because of economic, technical, environmental, and security reasons. It is not expected that nuclearpowered airplanes will be developed in the future.

Dirigibles are lighter than air. Modern industrial types transport heavy minerals or other raw materials from inaccessible areas to processing plants. The current models can carry a payload of 40 t (39 lnt, i.e. 88 360 lb) up to 360 km (194.4 nmi) [64].

17.4.3 Future Ship Technology

The slow speed two-stroke marine diesel engine will certainly consolidate its leading position with its optimal thermal effectiveness, resistance to wear, and high durability. It converts more than 50% of the chemical and thermal energy to mechanical work because of its high thermal efficiency. Theoretically more than 60% thermal efficiency is possible. However, higher heat recovery is not possible currently because the exhaust gas heat is used to produce steam, hot water and fresh water, and to warm the air in the intake which lowers the real thermal efficiency of engine.

In the future, the power of the engine will assumebly increase. Considerable potential is still available in the application of new materials in the combustion chamber and in the turbocharger. This development also presupposes an improvement in environmental compatibility and in climate balance of new materials.

Currently, the highest concentrations of pollutants exist in the exhaust gas of HFO fuel. However, the change between current HFO to higher fuel qualities, especially to diesel oil, may show incompatibility in the following way in the future:

  • • Low sulfur diesel fuel may not lubricate engines as required; therefore, mechanical parts may need extra lubrication; and
  • The change from hot HFO to cold diesel fuel must be done smoothly to avoid the injection pump piston seizing up.

The use of an SCR catalyst is the primary method for decreasing NOx emissions. This can be implemented in up to 90–95% of all ships. Advantageously, SCR is an additional technology and does not influence fuel consumption.

The secondary method is adding water to fuel to produce a fuel emulsion and humidifying the air for combustion which can lower emissions by 10–15%. However, these measures can cause corrosion in the engine and in the exhaust gas after treatment system, and increase fuel consumption. On-board monitoring equipment can discover deteriorations caused by humidifying.

In the future, emission trading will more and more emphasize decreasing technologies of fuel consumption and exhaust gas emissions also on ships. For the precise analysis of quality parameter the implementation of a monitoring system in the combustion and in the exhaust gas after treatment system may become more widespread.

Strengthened use of wind and solar energy and improving fuel management are a realistic way of increasing the efficiency of marine engines. Although new renewable energy sources will be quickly developed, there will be no alternatives to internal combustion engines using navy fuel for the next 30–40 years. Broad range applications of technologies with synthetic and biogenic fuels in shipping are expected in the far future.

Ships on inland water ways are becoming a more important part of sustainable transportation. In the course of this process, inland and coast navigation produce pollution which has an effect on residents in especially sensitive regions such sea coasts and harbor areas. Expected that in this sector, applications of biogenic and synthetic fuels will be more quickly introduced than in offshore zones.

References

References 295

  1. Ford study shows Rankine waste heat recovery system on a light-duty vehicles could almost met fuel vehicle accessory load on highway cycle. http://www.greencarcongress.com/ waste\_heat\_recovery/

Chapter 18 Interaction Between Future Transportation Technology and Future Fuel Supply

It seems to be a remarkable fact that discoveries and inventions for transportation were made at nearly similar time intervals in history because technology, legislation, and financial conditions influence all sectors of transportation in a very similar way (see Table 18.1) [1].

Can technology generally solve the problems of mobility and save the longterm transportation? The answer is more sited and not simply to form.

18.1 Time Dependency

The lack of time limits for future development is the main unsolved problem of strategies. The dependence on ''time'' is common in all sectors of transportation but the interpretation of time intervals is different [2].

The construction, production, marketing or inspection, and maintenance phase of vehicles, airplanes and ships is measured in months or years. The reference value is based on the subjective sense of time, depending on temporal experiences of human beings. This scale could lead to false conclusions and uncertainties or even qualitative mistakes in the interpretation of trends and prognoses.

The most critical situations are expected in the interaction of fuel supply and engineering technology. The description of possible scenarios with analysis of future developments in transportation can foresee qualitative changes only in a limited way. For this reason, only some basic relationships between fuel supply and engineering technology can be examined.

18.2 Saving Fuel

Saving fuel is the most important measure for the protection of the environment and the climate. Development will be shaped by saving resources, decelerating fuel consumption, supporting technical developments, and producing new type of

(continued)

| History and tendencies in transportation | | |------------------------------------------|--| | | | | | | | | | | | | | | | | Table 18.1 | |

Year Vehicle Airplane Ship Fuel
1750 1768 steam car for military
• 1765 first steam engine
)
transport (4 km h-1
passenger transport
1786 steam car for
•
•		 1783 flight with captive balloon
1784 hydrogen balloon crosses
the English Channel
lighter than air
•
•		 mination of water in the
1812 steam surface condenser
1807 merchant vessel ''North
River'' with a steam engine
with eli
boiler
•
•		 ca. 1750 kerosene used as a lubricant
ca. 1800 lamp oil
•
•
1850 • 1813 stationary gas engine
1897 self ignition engine
1887 three-wheeled car
mpression
mmercial
mpression engine
atmospheric engine
1878 four-stroke
1865 two-stroke
1899 first co
without co
vehicle
(3 HP)
co
•
•
•
•
•		 1852 airship with steam engine
1870 balloons used as blockade
1890 airplane with steam
engine (50 m, 164 ft)
1890 gliding flight
(26 km, 85.3 ft)
breakers
•
•
•
•		 mission for
1877 merchant vessel ''Turbinia''
ca. 1880 higher steam pressure
with steam turbine (103 ft,
ca. 1885 multiple expansion
steering and propulsion
ca. 1870 screw propeller
ca. 1890 effective trans
27 kn)
engine
•
•
•
•
•		 mania,
1857–1859 drilling for oil in Ro
1892 distillation of diesel oil
1861 distillation of navy oil
1876 distillation of gasoline
Germany and in the USA
•
•
•
•
1900 1942 mechanical turn off
1903 mass production of
indicator with internal
• 1900 delivery open cab
1934 front wheel drive
truck
light
cars
•
•
•		 mmercial aircraft ''F
1903 airplane ''Flyer'' (12 s,
1939 jet aircraft ''HE-178''
1937 helicopter ''VS 300''
1909 crossing the English
53 m, i.e., 174 ft)
1930 jet engine
Channel
1919 co
13''
•
•
•
•
•
•		 ca. 1920 coal replaced by heavy
1903 high speed liner ''Vandal''
ca. 1940 first ship diesel engine
with diesel–electric
1913 ''Vandal'' rebuilt as a
navy fuel oil
mission
warship
trans
•
•
•
•		 (GB used 1 million liters of gasoline per
mobile market increasing
1945 increasing prices worldwide
1903 war production
1939 war production
1909 auto
year)
•
•
•
•
Table 18.1 (continued)
Year Vehicle Airplane Ship Fuel
•
•
•
•
•
•
•
•
•
•
1950
2000		 m
Micro controller technology
1980 carbon fiber material
Mass produced hybrid car
m CCS
performance and low rp
mental electric car
Constructions with high
mproved aerodynamics
mposite substance in
ca. 1975 supercharger
On-board diagnosing
mbined
1972 exhaust turbo
mbustion syste
weight, but low
construction
DI, HCCI, co
Kevlar''
charging
Experi
co
Co
''
• I		 1952 regular civil traffic with jet
airplane of the world ''SR 71''
Wire in ''Concord''
aircraft between London and
Higher bypass ratio and thrust
mbustion
First whole plastic and CFC
1967 rocket engine airplane
1976 fastest reconnaissance
Satellite based navigation
mperatures and
pressures in the co
material airplane
Johannesburg
1980 Fly by
chamber
Higher te
''X15''
•
•
•
•
•
•
•
•		 Decreasing SFC and exhaust gas
1960 nuclear powered merchant
1986 steam turbine replaced by
ca. 1990 use of LNG as fuel in
diesel electric propulsion in
1955 gas turbine in warships
Tendency to larger hull of
''Queen Elisabeth II''
merchant vessels
vessel ''Arctica''
liquid tankers
Pod propulsion
Ring propeller
Fast monohull
Solar power
Double hull
missions
Linear jet
Sky Sails
e
•
•
•
•
•
•
•
•
•
•
•
•
•		 mass for BTL
water injection with tenside mixtures
Tertiary recovery methods by hot steam
ca. 1980 introduction of synthetic and
% by water
ca. 1980 drilling down to 6,000 m
ment and resources
Excessive production of bio
Exploitation rates at 50
in deep soil layers
1970 2nd oil crisis
1956 1st oil crisis
biogenic fuels
Saving environ
worldwide
injection
and
•
•
•
•
•
•
•
•

Fig. 18.1 Relation between oil consumption and CO2 concentration in air

fuels. However, the introduction of new types of fuels into the market will take a long time. According to current perceptions, the development of biogenic and synthetic fuels will probably proceed slowly. The technology of the next decades will permit blending traditional fuels such as diesel and gasoline with synthetic fuels, biogenic fuels, or compressed natural gas but this single measure will only moderately improve complex efficiency.

The technical development of all means of transportation will take place over a number of human generations in comparison to the development of fuel production. The combustion of fuels and the existing of combustion end products in the atmosphere impact the environment and climate for much longer periods of time than the life cycle of road vehicles, airplanes, and ships. So, the decomposition time of CO2 takes hundreds of years; see Fig. 18.1.

The time period ''1 year'' has a different meaning in transportation and in the resource system. A circulation of 10 years in technical development is adequate compared to 1,000 years of transportation's effects on the environment and on resources. An optimal organized balance between both time levels is the main task of engineering technology, and environment, climate, and energy protection.

18.3 Summary and Recommendations: Scenarios of Future Transportation

The time intervals in which new technologies penetrate the market, play a decisive role in development. A new technology must be reliable, safe, and the operating costs have to be more favorable than existing technologies in road, air, and sea transportation, otherwise new solutions will not be accepted by consumers.

After the Second World War, futurologists already intensively searched for scenarios to analyze the future. Even transportation was considered in the context of quickly changing and developing cultural values to those time. Since this period in history, petroleum products have been used in 98% of the world's transportation [3].

Peak Oil (PO) time is the time point when the world oil consumption will reach its highest level at around 97 9 106 barrel per day, i.e., approximately 5 9 109 t per year. This time point is expected in this century [4]. Saving fuel between 0.1 and 1.0% with intelligent monitoring technology could mean a financial benefit from €140 to 1,400 thousand million, i.e., US \$200–2,000 thousand million.

Future transport will strongly depend on the market penetration of new fuel types. However, there are only restricted possibilities to substitute new fuel types for traditional fuels. For this reason, saving fuel will be the most important measure to take for a long time.

The longer the epoch of using petroleum in transportation, the bigger are the chances of developing technology, ecology, economy, society, and politics. Saving fuel is the only way into the future.

References

  • 1. Jahresbericht (2006) InstitutfürZukunftsstudienundTechnologiebewertung. Berlin, April 2007. http://www.izt.de
  • 2. Hopp V, Berninger G, MathematischeFunktionen zur BeschreibungvonVorgängen in NaturundTechnik. GITFachzeitschrift Lab. 8/87, pp 682–691
  • 3. Kahn H (1980) Die Zukunftder Welt 1980–2000, 2nd edn. Fritz MoldenVerlag, München. ISBN: 3-217-00376-4
  • 4. Ölfördermaximum. http://de.wikipedia.org/wiki/Globales\_Ölfördermaximum

Appendix A Applied Units and Conversions

Table A.1 Base units of the International System of Units (SI) (Système International d'Unités)

Description Name Symbol
Length Meter m
Mass Kilogram kg
Time Second s
Electric current Ampere A
Absolute temperature Kelvin K
Amount of a substance Mole Mol
Light intensity Candela Cd
Flat angle Radian R
Rigid angle Steradian Sr

Table A.2 Supplementary units of the International System of Units (SI) (Système International d'Unités)

Description Name Definition
Frequency Hertz -1
1 Hz
= s
Strength Newton 1 N = 1 kg m s-2 =
105 dyn
Pond 1 p = 9.807 9 10-3 N
Dyn 1 dyn = 10-5 N
Conversions
Poundal 1 pdl = 0.138 N
Pound-force 1 lbf = 4.448 N
Ton-force 1 tonf = 9.964 kN
Mechanical tension Pascal 1 Pa = 1 N m-2
Phys. 1 atm = 1.01325 9 105
Pa = 760 Torr = 1.01325
atmosphere bar = 1.03327 at

(continued)

Table A.2 (continued)

Description Name Definition
Techn. atmosphere 1 at = 0.980623 9 105
Pa = 735.559 Torr = 10 m
WS = 104 kp
m-2 =
0.96780 atm
Torricelli 1 Torr = 133.3 Pa = 1.333 mbar = 1 mm Hg
Pascal 1 Pa = 9.86923 9 10-6 atm
= 7.50062 9 10-3
Torr = 10-5 bar
Bar 1 bar = 1 dyn m-2 =
105 Pa
Kilopond per m2 1 kp m-2 =
9.807 Pa = 9.678 9 10-5
atm = 10-4 at
Conversions
Pound per square inch 1 psi = 6,894.757 Pa
Pound-weight per square foot 1 lbf ft-2 =
47.88 Pa
Poundal per square foot 1 pdl ft-2 =
1.488 Pa
Ton-weight per square foot 1 ton ft-2 =
107.3 kPa
Energy Joule 1 J = 1 N m = 1 Ws = 0.2388 cal = 0.102 kp m
= 2.778 9 10-7 kWh
Volt-Ampere second 1V A s = 1 J = 107 erg
= 0.101kp m = 0.238846 cal
= 6.241 9 1018 eV
Electron volt 1 eV = 1.60219 9 10-19 J
= 1.6335 9 10-20 kp
m
= 96.485 kJ mol-1 =
23.061 kcal mol-1
Calorie 1 cal = 4.187 J = 0.427 kp m = 3.97 9 10-3 BTU
Meter kilopond 1 kp m = 9.807 J = 2.342 cal = 6.122 9 1019 eV
Kilowatt hour 1 kW h = 1.341 HP h = 860 kcal = 367,097 kp
m = 3.6 9 106 J
= 3,412 BTU
Conversions
Pound-weight foot 1 lbf ft = 0.138 kp m = 1.356 J
British thermal unit 1 BTU = 0.252 kcal = 107.6 kp m = 1 055.56 J
Ton of coal equivalent 1 tce = 2.931 9 1010 J
Ton of oil equivalent 1 toe = 4.187 9 1010 J
Horse 1 HPhr = 0.7457 kWh = 641.616 kcal = 273 959
power hour (UK, US) kp m = 2.649 9 106 J
Performance Watt 1 W = 1 J s-1 =
0.856 kcal h-1 =
1.36 9 10-3
HP = 0.101 972 kp m s-1
Conversions
Horsepower 1 HP = 550 lbf ft s-1 =
745.670 W
Pound-weight foot per second 1 lbf ft s-1 =
1.356 W
British thermal unit per hour 1 BTU hr-1 =
0.2931 W
Electricity Volt 1 V = 1 W A-1
Temperature Temperature difference 1 K = tC
+ 273.15 = 5/9 (tF-32) + 273.15
Degree Celsius 1o
C=tK- 273.15
tc
= 5/9 (tF
- 32)
Degree 1F = 9/5
(tk
-273.15) + 32
Fahrenheit tF
= 9/5 tc+ 32

Table A.3 Additional units of the International System of Units (SI) (Système International d'Unités)

Description Name Symbol Definition
Time Minute min 1 min = 60 s
Hour h 1 h = 3.6 9 103 s
Day d 1 d = 8.64 9 104 s
Year a 1 a = nrl. 3.155 9 107 s
Mega year Ma 1 Ma = 106 years
= 3.155 9 1013 s
Giga year Ga 1 Ga = 109 years = 3.155
9 1016 s
Flat angle Degree 1 = (p 180-1
) rad
Length Meter m 1 m = 100 centimeter (cm) = 103 millimeter
(mm)
Kilometer km 1 km = 1,000 m = 106
mm = 0.621 mi
Conversions
Statute mile mi 1 mi = 1 760 yd = 1.609 km
Nautical mile nmi 1 nmi = 1.852 km
Inch in 1 in = 2.54 cm
Foot ft 1 ft = 12 in = 0.305 m
Yard yd 1 yd = 3 ft = 0.914 m
League lq 1 lq = 3 mi = 4.828 km
Fathom fa 1 fa = 6 feet = 1.829 m
Cable cl 1 cl = 608 feet = 185.31 m
Sea league slq 1 slq = 3 nmi = 5.556 km
Area Square meter m2 1 m2 = 104 square centimeter (cm2
) = 106 square
millimeter (mm2
)
Square kilometer km2 1 km2 = 100 hectare (ha) = 104 Ar (a) = 106 m2
Conversions
Square inch in2 1 in2 = 6.45 cm2 = 6.45
9 10-4 m2
Square foot ft2 1 ft2 = 144 sq in = 0.093 m2
Square rod 2
r		 1 r2 = 30.25 sq ya = 25.29 m2
Square yard yd2 1 yd2 = 9 sq ft = 0.836 m2
Acre ac 1 ac = 4,840 sq yd = 4 047 m2
Square mile mi2 1 mi2 = 2.589 km2
Volume Liter l 11 = 1 dm3 = 0.264 gal (US) = 0.22 gal (UK)
Cubic meter m3 1 m3 = 103 cubic decimeter (dm3
) = 103 liter (1)
= 106 cubic centimeter (cm3
) = 106
milliliter (ml)
Conversions
Cubic foot cu ft 1 ft3 = 1,728 in3 = 28.317 dm3
Cubic yard cu yd 1 yd3 = 27 ft3 = 0.765 m3
Cubic inch cu in 1 in3 = 16.387 cm3
Pint (US) pt (US) 1 pt (US) = 0.473 l
Pint (UK) pt (UK) 1 pt (UK) = 0.568 l
Quart (US) qt (US) 1 qt (US) = 2 pints (US) = 0.946 1
Quart (UK) qt (UK) 1 qt (UK) = 2 pints (UK) = 1.137 1
Gallon (US) gal (US) 1 gal (US) = 4 quarts (US) = 3.785 l
Gallon (UK) gal (UK) 1 gal (UK) = 4 quarts (UK) = 4.546 1
1 bbl = 42 gal (US) = 158.987 1 = 0.159 m3
Barrel (US) bbl
Dry barrel (US) dbbl 1 dbbl = 0.1156 m3
Gross register tonnage GRT 1 GRT = 100 ft3 = 2.8317 m3

(continued)

Table A.3 (continued)

Description Name Symbol Definition
Mass Kilogram kg 1 kg = 103 gram
= 106 milligram
= 2.205 lb
Ton t 1 t = 103 kg
Kiloton kt 1 kt = 106 kg
Conversions
Pound lb 1 lb = 16 ounces (oz) = 0.454 kg
Ounce oz 1 oz = 28.35 g
Hundredweight (UK) cwt 1 cwt = 112 Ib = 50.802 kg
Long ton (UK) ltn 1 ltn = 20 cwt = 2,240 Ib = 1.016 metric t =
1,016 kg
Short ton (US) shtn 1 shtn = 2,000 Ib = 0.907 metric t = 907 kg
Slug sl 1 sl = 14.594 kg
Density Kilogram per liter kg dm-3 1 kg dm-3 =1tm-3 = 1 g cm-3 = 103 kg m-3
Pound per cubic foot lb ft-3 1 lb ft-3 = 16.018 kg m-3 = 0.016018 kg t-1
Pound per gallon (UK) 1 lb gal -1 (UK) 1 lb gal -1 (UK) = 0.099776 t m-3
Pound per gallon (US) lb gal-1 (US) 1 lb gal-1 (US) = 0.11983 t m-3
Speed Meter per second m s-1 1ms-1 = 3.6 km h-1 = 2.237 mph
Foot per minute ft min-1 1 ft min-1 = 5.08
9 10-3 m s-1 = 1.83
9 10-2
km h-1 =
1.14 9 10-2 mph
Miles per hour mph 1 mph = 1.609 km h-1 = 0.447 m s-1
Knot kn 1 kn = nautical or sea mile per hour = nmi h-1 =
1.852 km h-1 = 0.514 m s
-1
Fuel Liter per 100 km 1 9 100 km-1 1 l 9 100 km-1 = 282/mpg (UK) = 235/mpg
consumption (US)
Conversions
Miles by gallon (US) mpg (US) 100 km-1
1 mpg (US) = 235.21 l 9
Miles by gallon (UK) mpg (UK) 1 mpg (UK) = 282.48/l 9 100 km-1
Miles by gallon
(UK/US)		 mpg (UK/US) 1 mpg (UK) = 1.2 mpg (US)
Gram per kilowatt hour g kWh-1 1 g kWh-1 = 10.527
9 10-6 oz BTU-1
Gram per horsepower hour g HPh-1 1 g HPh-1 = 1.360 g kWh-1
Lower heating value of fuel LHV 1 LHV = 10,200 kcal kg-1 = 42 707 kJ kg-1
Specific emissions Gramm per kilometer g km-1 1 g km-1 = 56.8
9 10-3 oz mi-1
Ounce per mile oz mi-1 1 oz mi-1 = 17.543 g km-1
Radiation forcing Milliwatt per square meter mW m-2 1 mW m-2 =
636 lbf ft (s yd2
-1
)
Dynamic viscosity Poise P 1 P = 0.010 (kp s) m-2 = 0.1 N s m-2
Conversions
Pound per foot and second lb (ft s)-1 1 lb (ft s)-1 = 1.487 N s m-2
Pound-force second per
square foot		 lbf s ft-2 1 lbf s ft-2 = 47.88 N s m-2
Kinematic
viscosity		 Square meter per second m2
-1
s		 1 m2
-1 = 106 cSt = 3.6
9 103 m2 h-1
s
Centistoke cSt 1 cSt = 10-6 m2 s
-1 = 10-2 St
Conversions
Square foot per second ft2 s
-1		 1 ft2 s
-1 = 0.0929 m2 s
-1
Square foot per hour ft2 h-1 1 ft2 h-1 = 2.5806
9 10-5 m2 s
-1

Table A.4 Prefixes of the SI International System of Units ((Système International d'Unités)

Factor Name Symbol
1018 Exa E
1015 Peta P
1012 Tera T
109 Giga G
106 Mega M
103 Kilo K
102 Hecto H
10 Deca Da
10-1 Deci d
10-2 Centi c
10-3 Milli m
10-6 Micro l
10-9 Nano n
10-12 Pico p
10-15 Femto f
10-18 Atto a

Table A.5 Units of concentration

Name Symbol Definition
Percent parts per hundred %
Parts per million ppm (v) 10-6 to
volume
Parts per million ppm (m) 10-6 to
mass
Parts per billion ppb 10-9
Parts per trillion ppt 10-12

Table A.6 Conversion factors

Unit PJ TWh 106 t
CU coal unit		 106 t
ROU
Crude Oil Unit
1 Petajoule (PJ) 1 0.2778 0.0341 0.0239
1 Terawatt hour (TWh) 3.6 1 0.123 0.0861
106 t
CU		 29.308 8.14 1 0.7
106 t
ROU		 41.69 11.63 1.429 1

Table A.7 Calculation of weight to volume

| Physical properties | | | | | |----------------------|------------------------------|-------------|---------------|--| | Fuel sorts | Density by 15C (59F) | | 1 ton equals | | | | g ml-1
(lb ft-3
) | liter
l | barrel
bbl | | | Mineral oil (medium) | ca. 0.862
(53.82) | ca. 1,160 | ca. 7.3 | | | Gasoline | 0.725–0.780
(45.26–48.69) | 1,280–1,380 | 8.1–8.7 | | | Diesel oil | 0.820–0.845
(51.19–52.75) | 1,180–1,220 | 7.4–7.7 | |

About the Author

Professor Palocz-Andresen studied mechanical engineering and energy systems at the TU Montan University Mining Academy Freiberg, Saxony Germany. Finishing his PhD in 1978, he later became a scientist at the University of Karlsruhe at the Engler-Bunte-Institute and received his habiliation in 1993. At Maihak AG, Hamburg, he was the head of Environmental Application Analysis. He is a professor for Environmental and Climate Protection at the University of West Hungary in Sopron (Oedenburg). At the Leuphana University in Lüneburg he is has been offered a guest chair for Sustainable Transportation.

Professor Palocz-Andresen holds 50 German and 3 international patents which are registered in approximately 40 countries. He has directed 35 technical scientific projects in the energy industry, in gas supply technology, in water and waste water analysis technology, in mobility research, in micro measurement techniques, and in climate protection.

Professor Palocz-Andresen is a member of the Committee ''New Innovations'' of the Chamber of Commerce Hamburg and of the ''Meeting of the Respectable Merchants'' in Hamburg.

310 About the Author

In this book, covering all areas of transportation such as road vehicles, airplanes, and ships, solutions for economical and environmentally friendly technology are being examined. Fuel consumption, combustion processes, control, and the limitation of pollutants in exhaust gas are important environmental problems, for which guidelines such as 98/69/EC, 99/96, and 582/2011 determine the measuring technology and the processes for the reduction of fuel consumption and exhaust gas emissions. In addition to technological solutions, the consequences of international legislation and its effects on environmental and climate protection, and sustainability in the area of transportation are discussed.

A Approach control service, 215
Acceleration and brake phase, 211 Aromatic hydrocarbon, 15, 17, 28
Acceleration resistance, 55 Arrival route, 214, 218
Acid rain, 83, 228 Artificial laminar flow, 280
Active filter system, 38, 291 Asphaltene, 28
Active sound reduction, 278 Atmosphere, 93, 241
Additive, 15, 19, 26 Automatic transmission, 123
Aerodynamic condition, 279 Auxiliary device, 95, 175, 222
Aerodynamic resistance , 114, 124, 278 Average noise emission level, 242
Aeronautical information, 215 Aviation infrastructure, 214, 215
Aerosol, 228
Aggressive driving characteristic, 175
Agricultural area, 246 B
Air conditioning, 110, 123, 176 Basic pollution level, 175
Air corridor, 234 Battery, 268, 281
Air resistance, 110, 118, 126 Beacon technology, 221
Air space, 45 Benzene, 15
Air traffic control clearance, 214 Biogenic fuel, 21, 26, 246
Air traffic service, 214 Biomass, 22, 124, 227
Airbag, 55, 98 Blended fuel, 287
Airfoil, 51, 112, 113 Boiling point, 19
Airframe, 113, 126, 132 Boundary layer, 280
Airline timetable, 233 Braking, 39, 123, 211
Airplane, 55, 65, 92 Bulk carrier, 75, 159, 254
Airplane manufacturer, 205, 277 Bunker fuel, 258, 288
Airspace block, 219 Bunker tank, 27
Airspace congestion, 219 Burner, 38, 65, 143
Airworthiness requirement, 178, 180, 182 Butane gas, 24
All-electric airplane, 282
Altitudes of flight, 232
Aluminum-lithium alloy, 277 C
Ambient or outside air, 175 Cabin noise, 51
Angle of attack, 279 Calculation of risk, 202
Anti-corrosion protection, 23 CAN bus communication, 193
(cont.)
C		 Cost of automobile, 248
Carbon dioxide, 1, 91 Crack component, 16, 19
Carbon monoxide, 1, 91 Cracking, 24, 28
Cargo heating, 237 Crankshaft, 143, 144, 265
Cargo vessel, 50 Crew member, 75, 202, 203
Catalyst function, 193 Cross section area, 278
Catalyst heating, 193 Cruise ship, 49, 285, 289
Catamaran, 53, 54, 56 Cruising, 45, 254, 277
Certified analyzer, 175 Cryogenic tank, 21
Charcoal, 21 Cryogenization, 275
Charging air pressure, 197 Crystallization, 19
Chemical composition, 3 Curved trajectory, 279
Chemical reformation, 19 Customized change, 251
Cirrus cloud formation, 241 Cyclone, 234
Civil air transportation, 276 Cylinder, 138, 139, 167
Civil aviation, 24, 179, 252
Civilian airports, 284
Classification society, 183 D
Cleaning process, 39 Data recorder, 203
Climate change, 184, 234, 250 Data transfer system, 193
Climate gas, 1, 240 Deactivator, 16
Climate protection, 159, 240 Decomposition time, 149, 229, 300
Climbing, 217, 218, 224 De-icing, 279
Coastal surveillance, 221 Delayed start of the catalyst, 266
Cockpit, 66, 101, 252 Developing country, 228, 249
Cockpit and cabin personnel, 251 Diagnostic function, 195
Cold start, 62, 143 Diesel engine, 132, 159, 163
Collision with ground, 217 Diesel fuel, 13, 16, 23
Combustion chamber, 19, 86, 138 Digital distress signal, 221
Combustion process, 3, 21, 167 Diluted exhaust gas, 174
Commercial vehicle, 34, 35, 177 Dimethyl ether, 23
Composite and fiber glass strengthened mate Dirigible, 293
rial, 239 Disc brake, 39
Composite material, 51, 130, 277 Distillation process, 24
Compression ratio, 139, 278 Distress communication, 183
Compressor, 154, 167, 265 Distribution of lift force, 279
Computer aided traffic steering, 55 Double side bulk, 256
Computer display, 175 Driving assistant, 213
Computer supported diagnostic method, 192 Driving cycle, 174, 175, 177
Condensation of water vapor, 174 Driving route, 175
Conductivity, 51, 59 Durability, 248, 253, 274
Congestion, 55, 211, 270
Consumption quota, 3
Container ship, 46, 49, 115 E
Control cycle, 3, 176, 177 Economic calculation, 251
Control system, 101, 183, 291 Efficiency, 112, 124, 203
Controlled area, 215 Electric booster, 266
Conventional fuel, 26, 29, 246 Electric motor vehicle, 137, 271, 275
Conventional jet airplane, 258 Electric powered propeller, 281
Conversion of methane to hydrogen, 276 Electrochemical technique, 6
Conversion of real operation, 8 Electrodes of the fuel cell, 276
Convertible, 35, 248 Electromagnetic compatibility, 188
Cooling, 123, 143, 165 Electronic checkpoint, 211
Electronic detection of errors, 193 Flywheel, 268
Electronic stability program, 55 Fossil fuel, 23, 240, 275
Embedded electronic module, 254 Four-seat family-car, 264
Emergency fuel, 27 Framework, 184, 240
Emergency response operation, 221 Free flying area, 217, 224, 293
Emergency service, 249 Freight transportation, 4, 204, 264
Emission, 82 Freighter, 48, 281, 283
Empty weight, 47, 251, 281 Friction loss, 169
Emulsion, 23, 285, 293 Friction resistance, 280
Energy density, 26 Fuel cell, 274, 278, 290
Engine control device, 194 Fuel consumption, 1, 117, 237
Engine technology, 170, 171, 197 Fuel level detection, 10
Environmental and climate protection, 170, Fuel saving economy, 45
185, 240 Fuel saving technology, 159
Environmentally friendly vehicle fuel, 14 Fuselage, 113, 281, 283
Equipment of the aircraft, 216
Erosion in the compressor, 200
Established route structure, 292 G
Ethanol, 22, 26 Gas bubble, 16
Euro 5 and Euro 6 norms, 15 Gas station, 13
European directive, 10 Gas turbine, 26, 132, 149
Evaporation, 16, 24, 228 Gasoline, 13, 257
Excessive braking, 265 Gear, 121, 123, 132
Exhaust gas, 84, 160, 267 General aviation aircraft, 41
Exhaust gas after treatment system, 84, 160, Geothermal energy, 260
267 Glass fiber strengthened composite material,
Exhaust gas quality, 23, 163, 174 51
Exhaust gas refeeding, 39, 193 Glide ratio, 280
Extended flap, 218, 277 Global transportation, 245
Global warming on the Earth, 227
Gradual distillation, 16
F Ground control, 227
Fast re-distribution of weight, 279 Ground handling equipment, 277
Fast regulated loudspeakers, 278 Guideline, 42, 175
Fatal accidents, 249
Fermentation, 22
Ferry, 52, 257 H
Field elevation, 218 Harbor, 93, 204, 260
Fighter, 51, 253, 281 Hazardous material, 183
Filter system, 38, 292 Heat insulation, 51, 141, 241
Financing cost, 252 Heating value, 13, 19, 25
Fire fighting, 279 Heavy commercial vehicle, 177, 187
Fireproof and corrosion resistant material, 182
Fischer-Tropsch synthesis, 22, 29		 Heavy duty vehicles, 39, 63, 187
Fishing vessel, 51 Heavy marine fuel oil, 71, 258
Flammable substance, 27 Heavy metal, 238
Heavy storm with constant rain, 290
Flash point, 19, 24, 26 Helicopter, 41, 51
Fleet management, 75, 159, 210 Heterocyclic nitrogen, 28
Flight by radar, 218 Hexane, 24
Flight condition, 214 High durability, 72, 156, 253
Flight frequency, 233 High sea, 214
Flight profile, 218, 224 High speed four-stroke marine diesel engine,
Flight test for production, 251 162
Flow rate, 174, 175, 180 High strength aluminum alloy, 40
(cont.)
H		 L
Holding time, 176 Lack of time limit, 297
Homogenous mixing, 229 Landing and navigation fee, 252
Honeycomb sandwich construction module, Landing cycle, 199
283 Landing gear, 198, 218
Horizontal distance, 215 Last minute change in infrastructure, 293
Hot start, 16, 177, 187 Lead emission, 250
Hot-test, 176 Lead–acid battery, 270
Humidity, 9, 93, 234 Leakage of exhaust gas, 182
Hurricane, 234 Level of emission, 90, 241, 287
Hydrocarbon, 82, 180, 228 Life cycle of ship, 255
Hydrocracking, 275 Light duty vehicle, 10, 38, 62
Hydrodynamic, 109, 117, 260 Light gasoil, 27
Hydrodynamic lubrication, 19 Light plastic, 239
Hydrogen, 26, 274, 290 Lightning strike, 234
Hydrogen to carbon relationship, 19 Ligneous cellulose, 22
Limited airspace, 232
Limiting value, 3, 10, 90
I Linear extrapolation, 245
Ignition quality, 19 Liquid fuel, 13, 26, 185
Improved maneuvering, 278 Liquid hydrogen, 275
Industrial current connection, 270 Liquid paraffin, 19, 21
In-flight data exchange, 224 Liquidity of the shipping company, 255
Infrastructure, 11, 260, 293 Lithium-ion battery, 270, 274
Inhibition of the catalyst, 276 Load of the engine, 9, 65
Initial climb, 217 Local environment, 211
Injection system, 16, 137, 167 Long distance transport, 263, 271
Inland and coast navigation, 294 Long range flight, 26, 280
Inland shipping, 116, 117, 225 Low boiling end point, 15
Inland waterway, 119, 188, 224
Inspection, 191, 192, 205
Insulation blanket, 51 M
Insurance cost, 252 Main engine, 28, 99, 237
Integrated telecommunication system, 209 Main propulsion, 117
Intelligent monitoring technology, 301 Maintenance cost, 47, 127, 192
Intelligent recharging station, 272 Maintenance philosophy, 199
Internal combustion engine, 125, 271, 291 Malfunction, 105, 196, 205
International trade, 28 Maneuvering load, 279
Interpretation of time intervals, 297 Marine diesel engine, 160, 168, 285
Irregular operation of engine, 193, 195 Marine pollution, 221
Market forecast, 255
Mass transportation, vi, 241, 272
J Maximal exhaust gas temperature, 265
Japanese 10?15 mode, 177 Maximum freight load, 47
Jet engine, 149, 200, 259 Maximum takeoff weight, 47, 254
Jet fuel A, 24 Mechanical deterioration, 195
Jet fuel B, 24 Medium speed, 160, 162
Megacities, 271, 292
Member state, 178
K Merchant fleet, 51
Kerosene, 13, 24, 26 Merchant ship, 170, 254
Kevlar, 51 Metal container, 270
Metal hydrid, 21 O
Meteorological and navigation information, Obstructions in the vicinity of the airport, 216
220 Oceanographic forecast, 221
Methane, 26, 83, 276 Octane number, 16
Methanol, 22, 26, 276 Oil fired boiler, 51
Methyl tertiary butyl ether, 16 Oil production, 245
Metric unit system, 1 On-board electricity, 290
Micro controller, 5, 8 Open rotor jet engine, 252
Micro particle sensor, 197 Operating cost, 203, 251
Micro, mild and full hybrid vehicle, 269 Operation parameter, 138, 141, 155
Middle distance airplane, 114 Optical sensor, 209, 222
Middle distillate, 27 Optimal bunkering, 260
Mid-size car, 4, 62, 257 Organic lithium electrolytic solution, 270
Mid-size performance, 268 Overhaul interval, 202
Military airplane, 41, 51, 99 Oversized glider, 280, 282
Military airport, 284 Oxygen, 13, 95, 195
Military aviation, 51 Ozone, 227, 228, 241
Misfires, 195, 197
Mixed fuel, 22
Mixture adaptation, 193 P
Mixture tank, 27 Particle, 81, 197, 291
Mock up, 251 Particle filter, 160, 268, 291
Modified propeller drive, 278 Passenger airplane, 257, 281, 293
Molecule, 24, 28, 241 Passenger car, 175–177
Monitoring operation condition, 203 Passenger kilometer, 1, 241
Motor octane number, 16 Passenger mile, 1
Motor vehicle, 18, 173, 272 Passive filter system, 38
Payload, 55, 113
Peak travel time, 41
N Pentane, 24
Narrow body airplane, 45 Performance, 49, 128, 144
National authority in aviation, 178 Permissible engine temperature, 271
Natural gas, 19, 255, 276 Petrol, 13, 15, 27
Navigation, 209, 219, 235 Petroleum refining, 27
Navigational warning, 221 Photovoltaic solar power, 290
Navy gasoil, 27 Pilot-controller communication, 217
New distribution system, 288 Pilot rating, 217
New energy storage system, 259 Piston engine, 278
New propfan engine, 278 Pollutant, 126, 211, 292
New technology, 242, 268, 300 Position of vehicle, 209
Nitrogen dioxide, 1, 91 Positive displacement compressor, 266
Nitrogen monoxide, 1, 91 Power factor, 271
Nitrogen oxide emission, 185, 285 Pre-defined norm, 4
Noise insulation of the fuselage, 278 Present data, 6
Noise level, 242 Pressure regulator, 60
Nomenclature of components, 193 Pressure sensor, 86, 92, 103
Nominal condition, 8, 59 Preventive maintenance, 202, 205
Non-perishable good, 258 Prices of gasoline and diesel oil, 276
Normal aging process, 195 Private jet, 41
Nose landing gear, 198 Professional decommissioning, 239
Nuclear power, 293 Propane, 19
Number of revolution, 97, 160, 265 Propeller, 116, 128, 278
P
(cont.)		 Satellite and terrestrial radio communication,
Propulsion system, 115, 121, 132 220
Protected sea area, 72 Scenario, 83, 240, 300
Public parking place, 272 Seaborne trade, 47
Public transportation, 241, 255 Seagoing ship, 4, 27
Secondary air system, 193, 195
Sediments of liquid paraffin crystal, 19
Q Self ignition engine, 139, 257, 264
Qualification of the crew, 217 Sensor signal, 9, 98, 205
Separator system, 28
Service time interval, 279
R Settling tank, 27, 72, 73
Radar coverage, 227 Ship construction, 33, 128, 168
Radio and satellite navigation, 224 Ship exhaust gas, 9
Radio navigation procedure, 216 Shipping schedule, 204
Radio wave, 214 Shore power, 204, 260
Rear area of the wing, 277 Short distance airplane, 251
Rebuilt airplane, 276 Short time power, 270
Recreational and offshore ship, 220 Single-aisle airplane, 252, 283
Recycling, 238–240 Single sky initiative, 292
Recycling of ships, 240 Slow speed two-stroke marine diesel engine,
Refined maritime type of petroleum, 258 168, 170, 293
Refinery and manufacturer, 288 Slow steaming, 129, 242
Refinery process, 19 Slurry fuel, 28
Reformation of methanol, 276 Smooth driving, 40
Refueling, 260, 275 Solar, 259, 283, 290
Refueling time, 275 Solar cell powered airplane, 283
Regular commercial service, 279 Solar cell technology, 290
Regular supervision, 183 Soot, 23, 91, 288
Renewable energy source , 260, 285, 292 Spacecraft, 274
Replacing old ships, 255 Spark ignition engine, 137, 138, 193
Research octane number, 16 Spatial disorientation, 217
Resistance to wear, 293 Spoiler, 51, 109, 277
Retrofitting cost, 276 Spoilers in landing gear, 277
Revolution sensor, 197 Spraying, 24, 140, 171
Reynolds number, 115, 280 Stainless steel, 85, 129, 180
Road traffic, 87, 209, 230 Starting phase, 4, 9
Road vehicle, 34, 55, 121 Station wagon, 33, 35, 110
Roller test bench, 175 Statutory inspection, 184
Rolling resistance, 111, 118, 124 Steady wind, 289
Rough running, 195, 197 Steam boiler, 237
Route network, 233 Steam engine, 51, 128, 298
Rudder assembly, 277 Steam turbine, 51, 298
Runtime, 173, 202 Steel and aluminum, 118, 166, 239
Steel sheet, 40
Stopping, 131, 174
S Storage capacity, 205
Safety communication, 221 Storage of electricity, 273
Safety standard, 25, 179, 292 Storage of hydrogen, 21, 275
Sampling orifice, 180 Storage of the data, 258
Sandwich construction, 46, 283 Storage tank, 27
Stratosphere, 227, 228 Tropical storm, 234
Strengthened wall, 270 Troposphere, 227, 232
Submarine, 132, 274, 290 Trucking firm, 211
Substantially changed part, 173 Turbine engine, 24, 182
Substitute new fuel type for traditional fuel, Turbine wheel, 197
301 Turbocharger, 137, 167, 265
Sugar cane, 22, 27, 278 Turbofan engine, 101, 102, 150
Sulphur, 19, 184, 287 Turbo lag, 266
Sulphur content, 19, 28, 184 Turboprop engine, 46, 132, 251
Sulphur dioxide, 83 Turboshaft engine, 149
Sunflower, 22, 23 Twin-engine, 68
Super fuel, 16 Type approval, 59, 173, 186
Supply tank, 27 Type certification, 173, 181, 258
Supporting service, 221
Suspension, 40, 121, 131
Sustainable transportation, 231 U
Synthetic fuel, 30, 240 Unburned hydrocarbon, 93, 180, 228
System trials, 251 Unloaded weight, 39
Unmanned aircraft with hydrogen fuel cell,
282
T Unmanned airplane, 252
Takeoff weight, 47, 217, 254 Upper class car, 38
Tank, 49, 66, 72 Upstream to the catalyst, 9
Tank leak diagnosis, 193, 195 Urban sprawl, 55
Tank ventilation system, 193, 195
Tank volume, 39, 255
Taxiing, 278 V
Taxiing noise level, 242 Vacuum gasoil, 27
Technical improvement, 251 Vapor lock, 16
Teflon bag, 174 Vapor pressure, 16
Temperature sensor, 160 Variable wing profile, 277
Test bench, 6, 59, 84 Vehicle, 34, 55, 109
Test procedure, 175 Very large airliner, 258
Thermal effectiveness, 170, 293 Vessel, 74, 104, 219
Three-cylinder engine, 265 Viscosity, 19
Thunderstorm zone, 234 Visible emission, 186
Tight steering, 40 Volatile component, 16
Tightness of the filler cap, 195 Volatility, 16, 90
Tornado, 234 Voltage regulator of the engine, 270
Total CO2
emissions, 245		 Volume specific heating value, 13
Total life of parts, 200
Tow kite system, 289
Tower control, 215 W
Traffic incident report, 215 Waiting time at harbor, 260
Traffic jam, 292 Waste product, 1
Traffic organization, 55, 211, 218 Water, 15, 16, 74
Trailing edge, 51, 279 Water–gas, 21
Trailing flap, 279 Water vapor, 82, 174, 228
Transmission factor, 39 Weather information, 215
Transportation by road, 53 Weight of airplane, 258
Transportation by water, 53, 258 Weight of vehicle, 231
Transporter, 279, 281 Weight saving, 277

W (cont.) Whole life cycle, 3, 84, 201 Wide body airplane, 45, 46 Wind, 69, 74, 93 Wing, 51, 113, 126 Wing aspect ratio, 280, 281 Wing box, 277 Wing geometry, 277 Wing stabilizer, 51 Woody sources, 22 World oil consumption, 245, 301 Z Zirconium dioxide, 6, 86