W Powertrain Edited by Helmut List Scientific Board K. Hoag Vehicular Engine Design Powertrain SpringerWienNewYork Kevin L. Engine Research Center, University of Wisconsin–Madison, Madison, Wisconsin, U. This book is simultaneously published by Springer-Verlag, Wien, and the Society of Automotive Engineers International.
This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically those of translation, reprinting, re-use of illustrations, broadcasting, reproduction by photocopying machines or similar means, and storage in data banks. The publisher can give no guarantee for all the information contained in this book. This also refers to that on drug dosage and application thereof.
In each individual case the respective user must check the accuracy of the information given by consulting other pharmaceutical literature. The use of registered names, trademarks, 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. © 2006 Springer-Verlag, Wien Printed in Austria SpringerWienNewYork is a part of Springer Science + Business Media springeronline.com Typesetting: Thomson Press (India) Ltd., Chennai, India Printing: Druckerei Theiss GmbH, 9431 St. Stefan im Lavanttal, Austria Printed on acid-free and chlorine-free bleached paper SPIN 10975923 With 170 Figures Library of Congress Control Number 2005927148 ISSN 1613-6349 ISBN-10 3-211-21130-6 SpringerWienNewYork ISBN-13 978-3-211-21130-4 SpringerWienNewYork Preface The mechanical engineering curriculum in most universities includes at least one elective course on the subject of reciprocating piston engines.
The majority of these courses today emphasize the application of thermodynamics to engine efficiency, performance, combustion, and emissions. There are several very good textbooks that support education in these aspects of engine development. However, in most companies engaged in engine development there are far more engineers working in the areas of design and mechanical development. University studies should include opportunities that prepare engineers desiring to work in these aspects of engine development as well.
My colleagues and I have undertaken the development of a series of graduate courses in engine design and mechanical development. In doing so it becomes quickly apparent that no suitable text- book exists in support of such courses. This book was written in the hopes of beginning to address the need for an engineering-based introductory text in engine design and mechanical development. It is of necessity an overview.
Its focus is limited to reciprocating-piston internal-combustion engines – both diesel and spark- ignition engines. Emphasis is specifically on automobile engines, although much of the discussion applies to larger and smaller engines as well. A further intent of this book is to provide a concise reference volume on engine design and mechanical development processes for engineers serving the engine industry. It is intended to provide basic information and most of the chapters include recent references to guide more in-depth study.
A few words should be said concerning the approach taken to the figures presented in this book. With the exception of the production engine schematics and photos residing primarily in the first chapter, each of the figures was created specifically for this book. The intent was to provide simpli- fied diagrams and plots presenting only the features being discussed at the time. Actual production drawings are often far more complex.
The goal was to emphasize the topic being discussed and allow the reader to clearly see the particular design feature and how it will apply to the production engine. Acknowledgements It was the vision of Prof. Helmut List to create a new series of books on engine development of which this book is a part. Such vision has resulted in a valuable contribution to the engine industry, and many of us have worked hard to ensure that this volume is a worthy contribution to the series.
I am especially indebted to Dr. Josef Affenzeller, who provided the guiding force and many consultations along the way. His guidance was invaluable. Over the course of the writing, Dr.
Affenzeller’s assistant, Clara Horvath, contributed much appreciated help. vi Preface Thanks to Springer-Verlag for the professional support and design of this publication. The following companies provided figures as noted throughout the book. Their contributions are greatly appreciated: AVL List GmbH, BMW GmbH, DaimlerChrysler, Ford Motor Company, Nissan Motor Co., Toyota Motor Corporation, Volkswagen AG A special thank you is reserved for Bruce Dennert at Harley-Davidson.
His partnership in many engine design instruction endeavors and his input and critique throughout the writing process are greatly valued. Finally, I am indebted to my colleagues at the University of Wisconsin Engine Research Center. Rolf Reitz, David Foster, Patrick Farrell, Jaal Ghandhi, Christopher Rutland, Philip Myers, and Scott Sanders provide a stimulating environment in which to work, and encouragement throughout the writing. This book is dedicated to those in the engine development community who have left our company too soon.
I consider it my good fortune to have had the opportunity to work with Dr. Neal Watson of Imperial College, Dr. Van Sudhakar of Cummins Engine Company, David Parkhurst of Mercury Marine, and Dr. Gary Borman of the University of Wisconsin.
Madison, Wisconsin May 2005 Contents 1 The internal-combustion engine: an introduction 1 1.1 Heat engines and internal combustion engines 1 1.2 The reciprocating piston engine 3 1.3 Engine operating cycles 4 1.4 Supercharging and turbocharging 6 1.5 Production engine examples 6 1.7 Recommendations for further reading 11 2 Engine maps, customers, and markets 13 2.2 Automobile, motorcycle, and light-truck applications 17 2.3 Heavy-truck applications 19 2.4 Off-highway applications 21 2.5 Recommendations for further reading 23 3 Engine validation and durability 24 3.1 Developing a durable engine 24 3.3 Friction, lubrication, and wear 33 3.4 Further wear and failure mechanisms 38 3.5 Recommendations for further reading 39 4 Engine development process 41 5 Determining displacement 50 5.1 The engine as an air pump 50 5.3 Engine uprating and critical dimensions 55 6 Engine configuration and balance 56 6.1 Determining the number and layout of cylinders 56 6.2 Vibration fundamentals reviewed 57 6.3 Rotating forces and dynamic couples 58 6.5 Balancing the forces in multicylinder engines 65 6.6 Gas pressure forces 69 viii Contents 6.7 Bore-to-stroke ratio optimization 70 6.8 Recommendation for further reading 71 7 Cylinder block and head materials and manufacturing 72 7.1 Block and head materials 72 7.2 Block and head casting processes 75 7.3 A look at block and head casting 78 7.4 Block and head machining processes 80 7.5 Recommendations for further reading 82 8 Block layout and design decisions 83 8.1 Initial block layout 83 8.2 Crankcase design decisions 83 8.3 Cylinder design decisions 91 8.4 Camshaft placement decisions 94 9 Cylinder head layout design 97 9.1 Initial head layout 98 9.2 Combustion chamber design decisions 97 9.3 Valve, port, and manifold design 101 9.4 Head casting layout 108 9.5 Cylinder head cooling 111 9.6 Oil deck design 112 10 Block and head development 113 10.2 High-cycle loading and the cylinder block 113 10.3 Modal analysis and noise 115 10.4 Low-cycle mechanical loads 117 10.5 Block and head mating and the head gasket 118 10.6 Cylinder head loading 120 10.7 Thermal loads and analysis 121 10.8 Recommendations for further reading 123 11 Engine bearing design 125 11.1 Hydrodynamic bearing operation 125 11.2 Split-bearing design and lubrication 127 11.4 Classical bearing sizing 132 11.5 Dynamic bearing sizing 133 11.6 Bearing material selection 135 11.7 Bearing system validation 138 11.8 Recommendations for further reading 140 12 Engine lubrication 142 12.2 Lubrication circuits and systems 145 Contents ix 12.4 Oil pans, sumps, and windage 149 12.5 Filtration and cooling 150 12.6 Lubrication system performance analysis 151 12.7 Recommendations for further reading 152 13 Engine cooling 153 13.1 Engine cooling circuits 153 13.2 Cooling-jacket optimization 155 13.3 Water pump design 157 13.4 The cooling system 159 13.5 Venting and deaeration 159 13.6 Recommendations for further reading 160 14 Gaskets and seals 162 14.1 Gasketed-joint fundamentals 162 14.2 Engine cover design 164 14.3 Clamping load parameters 165 14.4 Bolt torque and sealing load control 167 14.5 Shaft seal design 168 14.6 Recommendations for further reading 168 15 Pistons and rings 170 15.2 Piston crown and ring land development 172 15.3 Piston pin boss development 175 15.4 Piston skirt development 178 15.5 Piston ring construction 179 15.6 Dynamic operation of the piston rings 181 15.7 Cylinder wall machining 184 15.8 Recommendations for further reading 186 16 Crankshafts and connecting rods 188 16.1 Crankshaft construction and manufacturing 188 16.2 Crankshaft fillet development 189 16.3 Torsional vibration and dampeners 192 16.4 Crankshaft nose development 197 16.5 Crankshaft flange and flywheel development 198 16.6 Connecting-rod construction and development 199 16.7 Recommendations for further reading 200 17 Camshafts and the valve train 202 17.1 Valve train overview 202 17.2 Dynamic system evaluation and cam lobe development 203 17.4 Valve train development 210 17.5 Drive system development 214 x Contents 17.6 Future trends in valve train design 215 17.7 Recommendations for further reading 216 Subject index 219 1 The internal-combustion engine: an introduction 1.1 Heat engines and internal combustion engines It is appropriate to begin with a simple definition of the engine as a device for converting energy into useful work. The goal of any engine is to convert energy from some other form into “mechanical force and motion.” The terms “mechanical force” and “motion” are chosen to convey the idea that the interest may be both in work output – how much force can be applied to move something a given distance – and in power output – how quickly the work can be done. Turning attention to the energy that is being converted to do the desired work, our interest is in the chemical energy bound up in the molecular structure of a hydrocarbon fuel. Fundamental to any chemical reaction are the facts that it takes energy to break a chemical bond and that energy is released when new bonds are formed.
If the energy released in forming new bonds is greater than that required to break the old bonds, the result is an exothermic reaction and net energy available to do work. Fundamental to any combustion engine is the reaction of a hydrocarbon fuel with oxygen to form carbon dioxide and water. This combustion reaction is highly exothermic – a large amount of energy is released. The goal of the engine will be to utilize that energy repeatedly, efficiently, and cost-effectively.
The next question with which the engine designer is faced is that of developing a mechanical device that accomplishes these objectives. Beginning from this general discussion of combustion engines, one can now make distinctions between various types of engines. These distinctions may be based on thermodynamic process decisions, as well as on the mechanical hardware. The first distinction to be made is that between the heat engine and the internal-combustion engine, as shown in Fig.1 – they really are two different things, although they have often been confused or incorrectly identified.
By definition, a heat engine is an engine in which a working fluid undergoes various state changes through an operating cycle. The working fluid experiences a heat addition in which its pressure and temperature Heat Source Air or Oxygen Heat source may be coal combustion, Work nuclear reaction, Work etc. Fuel Combustion Heat Sink Products a b Fig. Heat engine (a) and internal-combustion engine (b) 2 Introduction increase.
It then goes through a process converting a portion of its energy to work. Cycle completion requires heat rejection from the fluid to the environment. A Rankine cycle steam turbine, using either coal combustion or a nuclear reaction to provide the heat source (and steam as the working fluid), is a practical example of a heat engine. The “air standard” Otto cycle and diesel cycle are theoretical representations of processes similar to those of a spark-ignition or diesel engine, but they assume the working fluid to be air, gaining energy from an external source.