&Dnlt®Ililll®ltfiw® JEnu~fiiiD® &lllt®IriiDCBlltfiw®~ &rnli®ITIIil®lifiw® IEIID~fiiiD® &illi®IriiDCIDlifiw®§ Edited by Robert L. Evans The University of British Columbia Vancouver, British Columbia, Canada SPRINGER SCIENCE+BUSINESS MEDIA, LLC Library of Congress Cataloging in Publication Data International Symposium on Alternative and Advanced Automotive Engines (1986: Vancouver, B.C.) Automotive engine alternatives. "Proceedings of the International Symposium on Alternative and Advanced Auto- motive Engines, held August 1I-12, 1986, in Vancouver, B.C., Canada"-T.p. verso. "Sponsored by EXPO 86 and the University of British Columbia"-Pref. Includes bibliographies and index. Contents: How shall we power tomorrow's automobiles?lCharles A. Amann - The stratified charge engine conceptiDuane Abata-The dual-fuel engine/Ghazi A. Karim - [etc.] 1. Automobiles - Motors - Technological innovations - Congresses. 1. Evans, Robert L. II. Expo 86 (Vancouver, B.C.) III. University of British Columbia. IV. Title. TL21O.l47 1986 629.25 87-6949 ISBN 978-1-4757-9350-5 ISBN 978-1-4757-9348-2 (eBook) DOI 10.1007/978-1-4757-9348-2 Proceedings of the International Symposium on Alternative and Advanced Automotive Engines, held August 1I-12, 1986, in Vancouver, B.C., Canada © 1987 Springer Science+Business Media New York Originally published by Plenum Press, New York in 1987 Softcover reprint of the hardcover 1s t edition 1987 AII rights reserved No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, microfilming, recording, or otherwise, without written permission from the Publisher PREFACE This book contains the proceedings of the International Symposium on Alternative and Advanced Automotive Engines, held in Vancouver, B.C., on August 11 and 12, 1986. The symposium was sponsored by EXPO 86 and The University of British Columbia, and was part of the specialized periods program of EXPO 86, the 1986 world's fair held in Vancouver. Some 80 attendees were drawn from 11 countries, representing the academic, auto motive and large engine communities. The purpose of the symposium was to provide a critical review of the major alternatives to the internal combustion engine. The scope of the symposium was limited to consideration of combustion engines, so that electric power, for example, was not considered. This was not a reflec tion on the possible contribution which electric propulsion may make in the future, but rather an attempt to focus the proceedings more sharply than if all possible propulsion systems had been considered. In this way all of the contributors were able to participate in the sometimes lively discussion sessions following the presentation of each paper. The internal combustion engine, as applied to automotive propulsion, is probably undergoing a more rapid rate of evolution than at any time since the early part of this century. This rapid change is due to several factors, not the least of which are regulations designed to improve fuel economy and reduce exhaust emissions. Both of these factors have led engine designers to be more innovative than in the past and have led to an increased market share for the diesel engine, which until recently was primarily limited to the heavy vehicle market, with one or two excep tions. Advances in digital electronics in recent years, and in particular the micro-processor, have provided the engine designer with a whole new arsenal of techniques for providing engine control. Electronic control systems have been rapidly introduced, particularly on spark-ignition engines, with the result that remarkable improvements in both fuel economy and exhaust emissions have been achieved. This rapid development in conventional engine technology has meant that the developers of truly alternative engines, such as the Stirling engine, are faced with a moving target as they try to break into a market which has been dominated by the reciprocating internal combustion engine for some six decades. v It was in this exciting climate of rapid change in engine design and development that the symposium was convened. If one conclusion were to be drawn from the symposium, it would have to be that the conventional internal combustion engine is likely to be the major automotive prime mover to the end of the century. It may appear as either a spark-ignition or diesel engine, or perhaps part way in between as a stratified-charge engine, but it is unlikely to be replaced by a radically new design. Through evolution, rather than revolution, engine designers will be trying to meet the twin challenges of improved fuel economy and reduced exhaust emissions. R.L. Evans Vancouver, B.C. vi CONTENTS How Shall We Power Tomorrow's Automobile? Charles A. Amann General Motors Research Laboratory •••••••••••••••••••••••••••••• 1 A Review of the Stratified Charge Engine Concept Duane Abata Michigan Technological University ••.•••••••••.•••••••••.•••••••• 37 The Dual Fuel Engine Ghazi A. Karim The University of Calgary •••••.••••••.••••••••••••••••••••.••••• 83 Automotive Applications of Stirling Engines G. Walker, O.R. Fauvel The University of Calgary ••••••••••••••••••••••••••••••••••••.•• 105 The Development Status of an Automotive Stirling Engine Noel P. Nightingale Mechanical Technology Inc •••••••••••••••••••••••••.••••••••••••. 125 The Adiabatic Engine for Advanced Automotive Applications Roy Kamo Adiabatics Inc. 143 Low Heat Rejection Diesel Engines R.H. Thring Southwest Research Institute 167 Present Status and Future View of Rotary Engines A. Nagao, H. Ohzeki, Y. Niura Mazda Motor Corporation • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • . • • . • • • • • • 183 The Stratified Charge Rotary Engine James w. Walker, Robert E. Mount John Deere Technologies Inc •••••.••••.••••••..••.••••.•..•••.... 203 Turbo-Compound Diesel Engines F .J. Wallace University of Bath 219 Recent Advances in Variable Valve Timing T.H. Ma Ford Motor Company 235 vii The Outlook for Conventional Automotive Engines Bernard I. Robertson Chrysler Corporation •••••••••••••••••••••••••••••••••••••••••••• 253 .............................................................. Index 265 viii HOW SHALL WE POWER TOMORROW'S AUTOMOBILE? Charles A. Amann Engine Research Department General Motors Research Laboratories Warren, Michigan ABSTRACT The thrust toward further gains in the fuel-utilization efficiency of the passenger-car engine, without sacrificing its many other desirable attributes, is continuing. The search for an attractive alternative powerplant has always been included in such efforts, but so far none has emerged. Prominent on the list of contenders today are the Stirling engine, the gas turbine, and the advanced diesel, including uncooled versions incorporating structural ceramics. Large scale production of none of these is projected for passenger cars in the foreseeable future. Meanwhile, improvements continue to be made to indicated thermal efficiency, mechanical efficiency, and volumetric efficiency of the spark-ignition engine. Supercharging and variable engine geometry are additional options, and the advent of electronic controls has proven beneficial. The spark ignition engine promises the ability to operate on the leading alternative fuels. Given the evolving scenario, that engine is expected to remain dominant in passenger cars to the end of this century. INTRODUCTION In just 15 years we will be into a new century. What kind of engine will power our passenger cars for the rest of this one? That is a very intriguing question. The gasoline-fueled homogeneous-charge spark-ignition engine has dominated the field for the past 2/3 of a century, but that has not always been so. In 1900 that powerplant was in third place, behind the steam engine and the battery-electric system. And there is no guarantee that today's spark-ignition engine will retain its preeminent position in the future. Certainly there is no shortage of competing alternatives. The possibilities are indicated on the heat-engine tree of Fig. 1. Both continuous-combustion and intermittent-combustion engines are candidates. In both categories, combustion may occur either internal or external to the engine. Of the resulting four possibilities, however, an Fig. 1. Heat-engine tree. attractive intermittently burning external-combustion engine has yet to be identified. In the continuous-external-combustion class, the Rankine-cycle steam engine has the longest history behind it. In recent years the substitution of various organic fluids for water in the steam engine has provided an interesting variant. The Stirling-cycle engine, which has existed since the early 1800s, is a continuous-external-combustion engine that uses a gaseous working fluid, avoiding the phase change that characterizes the Rankine cycle. The leading continuous-internal-combustion candidate is based on the Brayton cycle. The reciprocating Brayton-cycle engines was in use during the last half of the 1800s. Ir has even been proposed for passenger-car propulsion in modern times [1) , but the leading option in this engine class is the non-reciprocating version, the gas turbine. The intermittent-internal-combustion engine requires frequent periodic ignition of gulps of cylinder charge. That ignition may be accomplished either spontaneously, as the result of compression of the charge, or by some forced means, usually by an electrical spark. Going a step further in Fig. 1, ignition in the intermittent-internal combustion engine may be effected in either a homogeneous or a stratified charge of fuel and air. The compression-ignited stratified-charge engine is recognized as the diesel. Homogeneous-charge compression-ignition has been employed successfully in reciprocating engines [2,3), but limitations placed on operating speed and load by reaction kinetics make it an unlikely candidate for the passenger-car application [4]. In contrast, when ignition is forced by a spark, both homogeneous and stratified charges constitute viable possibilities for the automobile. 1Numbers in brackets designate references found at the end of this paper. 2