Internal-Combustion Engine in Theory and Practice, Volume 2 - Combustion, Fuels, Materials, Design

1985·26.62 MB·English

by  Charles Fayette

The Internal-Combustion Engine
in Theory and Practice
Volume 11: Combustion, Fuels, Materials, Design
Revised EditioE
by Charles Fayette Taylor
Professor of Automotive Engineering, Emeritus
Massachusetts Institute of Technology
THE M.I.T. PRESS
Massachusetts Institute of Technology
Cambridge, Massachusetts, and London, England
Copyright 0 1968 and new material 0 1985 by The Massachusetts Institute of
Technology
All rights reserved. No part of this book may be reproduced in any form by any
electronic or mechanical means (including photocopying. recording, or information
storage and retrieval) without permission in writing from the publisher.
Printed and bound in the United States of America.
First MIT Press paperback edition. 1977
Revised edition, 1985
Library of Congress Cataloging in Publication Data
Taylor. Charles Fayette, 1894-
The internal-combustion engine in theory and practice.
Bibliography: v. 2. p.
Includes index.
Contents: v. 2. Combustion. fuels. materials. design
I. Internal combustion engines. I. Title.
TJ785.T382 1985 621.43 84-28885
ISBN 0-262-20052-X (hard)
ISBN 0-262-70027-I (paper)
ISBN-13 978-0-262-20052-3 (hard)
ISBN-13 978-0-262-70027-6 (paper)
20 19 18 17 16 15 14
Preface
As in the case of Volume I, much of the material in this volume derives
from the author’s work, for many years, as Director of the Sloan Labo-
ratories for Aircraft and Automotive Engines. at the Massachusetts
Institute of Technology and as a consultant to government and industry.
Since Volume I1 was published in 1968 there have been no changes in
the fundamental principles discussed herein. However, as stated in the
preface to Volume I, the petroleum crisis of the 1970s and the adoption of
public laws requiring reduced undesirable exhaust emissions have caused
changes in emphasis on a number of aspects of engine design, application,
and operation. Recent developments in electronic computers and control
systems have greatly assisted in the improvement of fuel economy and
pollution control. These subjects are discussed in more detail at appropriate
points in this volume.
The recent emphasis on fuel economy and pollution control has also
stimulated theoretical searches for an automobile power plant better than
the conventional spark-ignition or Diesel engine. Such studies (refs. 23.00,
13.01) have found no alternative type that promises to have significant
advantages in fuel economy or pollution control, and, above all, none that
has nearly the all-around simplicity, safety, and adaptability of present
engines. It appears that the conventional types of spark-ignition and Diesel
engines will remain in their present predominant position in land and sea
transportation and for industrial and portable power for the foreseeable
future.
Although great pains have been taken to avoid errors, it is not possible
to eliminate them entirely in a work of this magnitude. It is hoped that
readers who discover errors will be so kind as to notify the author, in care
of The M.I.T. Press, so that they can be corrected in future editions.
Cambridge, Massachusetts C. FAYETTTAE YLOR
January 1984
Contents
Page
Introduction 1
Combustion in Spark-Ignition Engines I: Normal Combustion 10
Basic Theory and Experimed I0
Flame Propagation in Engines 15
Flame Travel and Pressure Development in Engine Cylinders 23
Exhaust Emissions 33
Combustion in Spark-Ignition Engines 11: Detonation and
Preignition 34
Detonation 34
Preignition 84
Combustion in Diesel Engines 86
Definitions 88
Photographs of the Combustion Process 88
The Three Phases of Combustion 89
Detonation in the Diesel Engine 95
Combustion-Chamber Design in Diesel Engines 110
Effects of Cylinder Size on Combustion in Diesel Engines 116
Exhaust Emissions from Diesel Engines 117
Fuels for Internal-CombustionE ngines 119
Petroleum Fuels 119
Gaseous Fuels 126
Nonpetroleum Fuels 127
Fuels for Spark-Ignition Engines 128
Detonation Characteristics of Fuels for S-I Engines 142
Effect of Fuel Composition on Preignition 153
Miscellaneous Properties of Fuels for S-I Engines 154
Effect of Fuel on Power and Efficiency of S-I Engines 155
Fuels for Diesel Engines 160
Unconventional Fuels 171
Mixture Requirements 173
Mixture Requirements for Spark-Ignition Engines 173
Effect of Fuel-Air Ratio on Exhaust Emissions 191
Mixture Requirements for Diesel Engines 192
viii CONTENTS
Page
6 Carburetor Design and Emission Control 193
Steady-Flow Carburetion 193
Transient Carburetion 204
Complete Automotive Carburetor 205
Aircraft Carburetors 207
Electronic Controls 211
7 Fuel Injection 214
Fuel Injection for Diesel Engines 214
Fuel Injection for Spark-Ignition Engines 234
Size Effects in Fuel Injection 238
8 Engine Balance and Vibration 240
Literature 240
Definitions 240
Symbols 241
Single-Cylinder Gas Forces 243
Inertia Forces and Moments 244
Engine Torque 263
Engines with Nonuniform Firing 275
Engines with Articulated Connecting Rods 275
Balance of Typical Engines 279
Engine Vibration 279
External Engine Vibration and Vibration Isolation 289
Engine Noise 295
9 Engine Materials 306
Structural Materials 307
Nonstructural Properties of Materials 333
Steel 333
Cast Iron 341
Aluminum 345
Magnesium 345
Bearing and Bushing Alloys 350
Miscellaneous Materials 351
Specific Choice of Materials 351
10 Engine Design I: Preliminary Analysis, Cylinder Number,
Size, and Arrangement 352
Introduction 352
Basic Decisions and Preliminary Analysis 352
Determination of Cylinder Number, Dimensions, and Arrangement 377
Examples 383
General Discussion on Examples 408
Experimental Development 409
11 Engine Design 11: Detail Design Procedure, Power-Section Design 423
General Problems in Detail Design 424
Screw Fastenings 433
Engine Illustrations 440
The Power Train 469
CONTENTS ix
Page
Cylinder Design 469
Piston Design 478
Connecting Rods 487
Crankshaft Design 492
Crankcase Design 504
Engine Bearings 509
12 Engine Design 111: Valves and Valve Gear, Gears and Auxiliary
Systems 52 1
Poppet Valves 521
Valves and Ports for 2-Cycle Engines 535
Valve-Gear Design 537
Gearing 556
Superchargers and Scavenging Pumps 562
Manifolding 564
Ignition Systems 566
Injection Systems 566
Cooling Systems, Liquid 567
Cooling Systems, Air 567
Lubrication Systems 568
Auxiliaries 569
Gaskets and Seals 570
Over-All Design Criteria 571
13 Future of the Internal-CombustionE ngine. Comparison with
Other Prime Movers 576
Minor Modifications to the Conventional Types 578
Unconventional Displacement Engines 579
Gas Turbines 585
External-Combustion Power 599
The Stirling Engine 601
Electric Power 601
Non-Air-Breathing Power Plants 602
Summary 604
Fuel Resources 604
14 Engine Research and Testing Equipment-Measurements-Safety 605
Basic Equipment 605
Measurement Equipment and Techniques 607
Complete Single-Cylinder Test Installations 619
Test Procedure 625
Safety 625
Symbols and Their Dimensions 629
Bibliography 637
Introduction 638
Chapter 1 642
Chapter 2 648
Chapter 3 659
Chapter 4 667
Chapter 5 680
X CONTENTS
Page
Chapter 6 682
Chapter 7 684
Chapter 8 688
Chapter 9 696
Chapter 10 703
Chapter 11 719
Chapter 12 733
Chapter 13 743
Chapter 14 752
Index 762
Introduction
Since it is some years since the first volume of this series was published, it
may be well to cite some of the important developments in the fields covered
by Volume I since its publication. Very briefly, these are as follows:
Thermodynamic Characteristics of the Fuel-Air Medium. By means of
computer techniques, thermodynamic charts similar to those included in
Volume I (Charts C-1 through C-4) have been constructed for a wider range
of fuel compositions, fuel-air ratios, temperatures, and pressures than
hitherto available (0.030-0.035).*
Fuel-Air Cycles. Based on computer programs of the appropriate
thermodynamic properties of the charge, the characteristics of fuel-air
cycles have also been computed over a much wider range of the important
variables than has previously been feasible (0.040-0.045).
Reference 0.040, The Limits of Engine Performance by Edson and
" "
Taylor, gives the characteristics of constant-volume fuel-air cycles based
on conditions at point 1 (beginning of compression). These data are more
convenient and more versatile than those incorporating the idealized
inlet and exhaust processes. The second edition of Volume I contains
data from this reference in place of Fig. 4-5 (p. 82) of the first edition,
which was based on cycles with the idealized 4-stroke inlet and exhaust
process.
For the convenience of those who have only the first edition of Volume I,
Figs. 0-1 through 0-6 herewith give the most important data from ref.
0.040 namely fuel-air cycle efficiencies and ratios of maximum to initial
pressure, p3/pl. Important conclusions based on ref. 0.040 include the
following :
Variations in humidity from 0 to 0.06, mass vapor to mass air, have no
effect on fuel-air-cycle efficiency.
Variations in residual-gas content fromf= 0 tof= 0.10 have a negligibly
small effect on efficiency.
Efficiency is little affected by the initial pressure pl, except where
FR = 1.0 (Fig. 0-3).
Increasing initial temperature T, reduces efficiency (Fig. 0-4) as well as
PJP1 (Fig. 0-6).
* Numbers in parentheses refer to items in the bibliography, pages 637-761.
1
2 1NTRODUCTION
F
Compression ratio
Fig. 0-1. Efficiency versus compression ratio for the constant-volume fuel-air cycle (Edson and
Taylor, 0.040).
3
INTRODUCTION
0.65
0.60
0.55
0.50
F
0.45
0.40
0.35
0.30
0.25
0.4 0.6 0.8 1.0 1.2 1.4 I .6
FR
Fig. 0-2. Efficiency versus Fn for the constant-volume fuel-air cycle (0.040).