1、Engine Combustion: Pressure Measurement and Analysis by David R. RogersEngine Combustion: Pressure Measurement and Analysis R388_EngineCombustion_Text.indb i R388_EngineCombustion_Text.indb i 6/23/10 12:06:33 PM 6/23/10 12:06:33 PMOther SAE titles of interest: An Introduction to Engine Testing and D
2、evelopment By Richard D. Atkins (Product Code: R-344) Engine Testing: eory and Practice, ird Edition By Michael James Plint and Tony Martyr (Product Code: R-382) Modern Engine Technology from A to Z By Richard Van Basshuysen and Fred Schaefer (Product Code: R-373) Internal Combustion Engine Handbook
3、 By Richard Van Basshuysen and Fred Schaefer (Product Code: R-345) For more information or to order a book, contact SAE International at 400 Commonwealth Drive, Warrendale, PA 15096-0001, USA; phone 877-606-7323 (U.S. and Canada only) or 724-776-4970 (outside U.S. and Canada); fax 724-776-0790; e-ma
4、il CustomerServicesae.org; website http:/books.sae.org. R388_EngineCombustion_Text.indb ii R388_EngineCombustion_Text.indb ii 6/23/10 12:06:34 PM 6/23/10 12:06:34 PMEngine Combustion: Pressure Measurement and Analysis David R. RogersWarrendale, Pennsylvania USA R388_EngineCombustion_Text.indb iii R3
5、88_EngineCombustion_Text.indb iii 6/23/10 12:06:34 PM 6/23/10 12:06:34 PM Copyright 2010 SAE International eISBN: 978-0-7680-3442-4All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, ph
6、otocopying, recording, or otherwise, without the prior written permission of SAE. For permission and licensing requests contact:SAE International Permissions400 Commonwealth DriveWarrendale, PA 15096-0001-USAEmail: permissionssae.orgFax: 724-776-9765 Library of Congress Cataloging-in-Publication Dat
7、a Rogers, David (David R.)Engine combustion : pressure measurement and analysis / David R. Rogers.p . c m .Includes bibliographical references and index.ISBN 978-0-7680-1963-61. AutomobilesMotorsCylinders. 2. AutomobilesMotorsCombustion. 3. PressureMeasurement. I. Title. TL214.C93R64 2010629.25dc22
8、2010021607SAE International400 Commonwealth DriveWarrendale, PA 15096-0001 USATel: 877-606-7323 (inside USA and Canada)Tel: 724-776-4970 (outside USA and Canada)Fax: 724-776-0970Email: CustomerServicesae.org Website: http:/books.sae.org Copyright 2010 SAE International ISBN 978-0-7680-1963-6 DOI 10.
9、4271/R-388 SAE Order No. R-388 Printed in USA R388_EngineCombustion_Text.indb iv R388_EngineCombustion_Text.indb iv 6/23/10 12:06:34 PM 6/23/10 12:06:34 PMv Contents Chapter 1 A Brief History of Engine Indicators.1 Chapter 2 The Measurement Chain: Encoders 21 Chapter 3 The Measurement Chain: Combust
10、ion Pressure Transducers 35 Chapter 4 The Measurement Chain: Additional and Alternative Transducers .91 Chapter 5 The Measurement Chain: Measurement Hardware 111 Chapter 6 The Measurement Chain: Measurement System Software .145 Chapter 7 Applications .175 Chapter 8 Abnormal Combustion: Measurement a
11、nd Evaluation .217 Chapter 9 Successful Measurements .255 Chapter 10 Speci cation and Integration into the Test Environment .287 Bibliography . 303 R388_EngineCombustion_Text.indb v R388_EngineCombustion_Text.indb v 6/23/10 12:06:34 PM 6/23/10 12:06:34 PMvi Contents References . 305 Index 309 About
12、the Author . 322 R388_EngineCombustion_Text.indb vi R388_EngineCombustion_Text.indb vi 6/23/10 12:06:34 PM 6/23/10 12:06:34 PMvii Indicator, or combustion pressure measurements, used to be the preserve of “experts” only. But, due to the general decrease in the cost of the measurement technology, and
13、 the increasing complexity of the task of developing an internal combustion engineincluding optimising all the available parameterscombustion pressure measurement is no longer an exclusive task. Today, it is much more likely that test cell operators, technicians, and engineers will be required to ha
14、ve a clear understanding of the measurement procedure and the equipment involved. e idea behind this book is to provide the inexperienced technical person, trying for perhaps the rst time to understand combustion pressure measurements, a source of basic information and guidance on what equipment is
15、available and how to use it in various common applications. e book has been developed as a handbook, to be used as an initial source of information and then, perhaps, to be consulted regularly as a reminder during daily work, or to point the reader to other good sources of information on the subject
16、. is book is not o ered as a detailed thesis on the subject of engine combustion and thermodynamics; there are many excellent sources of information available to supplement the information in this book, that will enable readers to develop their knowledge further on the topic of combustion and how to
17、 measure, understand, and optimise it. ere is much tribal knowledge in a specialized environment, and best practice, gained from experience, is o en shared among users and operators of combustion measurement equipment. is book is an attempt to bring together some of this knowledge and combine it wit
18、h suggested pathways to further, more detailed information. is should enable readers to go from understanding rst principles, to using equipment, gaining experience, and nally to being able to con dently purchase equipment of the correct price and performance for their needs. e important points to c
19、onsider with respect to combustion measurements are that this equipment is relatively expensive and sensitive, so that a correct understanding is a prerequisite for an e cient measurement process. It is important always to bear in mind that the only thing produced by combustion measurement is data.
20、If this data is in any way inaccurate, considerable time and money can be wasted. erefore, familiarity with the measurement system and its e cient operation is essential. In addition, combustion measurements typically create large data lesand while the cost of storing data is relatively low, the tim
21、e needed to reduce or mine this data, to get the important information from it, can be considerable and should not be overlooked. Data can, of course, be reduced, but it is important to understand the compromises in each stage of reduction, and, if possible, to maintain reversibility and traceabilit
22、y so that if it should be necessary to go backward, post- reduction, deeper into the detail of the raw data, that can still possible. I would like to thank the companies who have supported me in this project by providing and sharing details of their equipment, systems, and technologies for combustio
23、n pressure Introduction R388_EngineCombustion_Text.indb vii R388_EngineCombustion_Text.indb vii 6/23/10 12:06:35 PM 6/23/10 12:06:35 PMviii Introduction measurement. I am very grateful to them for this. In particular, I would like to thank Sandra Gildemeister of AVL List GmbH for her ongoing assista
24、nce throughout the project. David R Rogers, 2010 Companies who have provided support and information: AVL List GmbH () Kistler Instruments () d2t () FEV () Dewetron () Lehmann and Michels GmbH () Optrand Inc. () Delphi () Polytec GmbH () Wo l Control Corp (www.wol ) Jodon Inc. () R388_EngineCombusti
25、on_Text.indb viii R388_EngineCombustion_Text.indb viii 6/23/10 12:06:35 PM 6/23/10 12:06:35 PM 1 Chapter 1 A Brief History of Engine Indicators R388_EngineCombustion_Text.indb 1 R388_EngineCombustion_Text.indb 1 6/23/10 12:06:35 PM 6/23/10 12:06:35 PM2 A Brief History of Engine Indicators 1.1 Early
26、Engine Indicators 1.1.1 The First Indicators e process of measuring the pressure inside the cylinder of a reciprocating piston engine dates back to the dawn of the reciprocating engine itself. During the early development of the steam engine by James Watt and others, understanding the in-cylinder pr
27、ocess of energy release was fundamental to optimising the performance of the engine as a complete machine. e engine cycle operation can be represented by a diagram that plots instantaneous cylinder pressure against cylinder volume, known as an indicator diagram. Generally the process of taking such
28、measurements uses a device known as an engine indicator, which generates the diagram while the engine is running. Information from these measurements is an essential element in the goal of improving e ciencies and optimising in-cylinder motion and expansion of the working uids. In the early days, me
29、chanical devices were used to gather in-cylinder information. ese devices, known as indicators, were installed on the engine and were subjected to the working pressure in the cylinder; in addition, they were connected to the engine crosshead or cranksha . From these two fundamental measurement input
30、s (pressure and volume, volume derived from the cranksha /crosshead position) the characteristic loop of the pressure/work cycle could be recorded for analysis. e indicators used by the steam engine pioneers were very primitive. e rst steam engines had no cranksha . ey were generally beam-type engin
31、es, and the indicator was attached to the crosshead, which had longitudinal motion. e general arrangement is shown in Figure 1.1. An early improvement was the “moving tablet” indicator. is was a simple design and illustrates the measurement principle with great clarity as shown in Figure 1.2. The cy
32、linder pressure was applied via a valve to an indicator cylinder and to the moving piston, displacing it accordingly and moving the pencil in proportion to the working pressure. The cord in Figure 1.2 was connected to the moving crosshead or rotating crankshaft, and thus as motion occurred, the tabl
33、et would move linearly. The interacting movements of the piston/pencil and the tablet when the engine was running produced a closed-loop diagram that would be drawn on the tablet with each working cycle. This diagram constituted the basic recorded data. Once the measurement was completed, the tablet
34、 was removed. With the application of appropriate scaling factors for pressure and volume, the area represented by the closed-loop diagram could be established. Note that finding this loop area satisfies the basic requirement of the measurement technique: to understand the amount of energy released
35、or work done in the cylinder. In fundamental terms, pressure is measured as a function of the volume, and because the area of the recorded loop represents pressure multiplied by volume, the area can also be expressed in units of work. Thus the area of the enclosed loop represents the work done in th
36、e cylinder during that cycle. If the engine speed is known, power can be determined and this value can be compared with the actual power output from the engine. Thus, the indicator measurement can help the engineer identify the efficiency of the engine and can assist in further development to minimi
37、se losses. This still holds true for todays engineers making indicator measurements. Although the equipment is much more sophisticated, the same basic principles apply and the development goals are the same: R388_EngineCombustion_Text.indb 2 R388_EngineCombustion_Text.indb 2 6/23/10 12:06:35 PM 6/23
38、/10 12:06:35 PM 3 Early Engine Indicators | Chapter 1 Figure 1.1 Indicator attached to the crosshead of a beam engine. (Source: John Walter, Archiving Industry.) Figure 1.2 Moving tablet type of indicator, circa 1790s. (Source: John Walter, Archiving Industry.) R388_EngineCombustion_Text.indb 3 R388
39、_EngineCombustion_Text.indb 3 6/23/10 12:06:35 PM 6/23/10 12:06:35 PM4 A Brief History of Engine Indicators to understand the energy release process inside the cylinder with the goal of optimising efficiency. 1.1.2 Early Developments in Indicator Technology As steam engines evolved, more sophisticat
40、ed mechanical devices were developed and utilised, ones that could cope with the requirements for increasingly higher engine speeds and pressures. During this time the drum-type indicator was developed, and this basic design has served to execute the measuring task, using a simple mechanical techniq
41、ue, for nearly 200 years. Fundamentally, the same basic design as originally proposed is still in use today, which demonstrates the excellence of the engineering and design practice applied at that time. Figure 1.3 shows the basic construction of the drum-type indicator. Replacing the moving tablet
42、with a rotating drum, the drum-type indicator has the advantage of reduced friction, as well as being more compact. Cylinder pressure is applied via the tapered plug to the piston in the cylinder of the indicator. As the cylinder pressure increases, force is applied to the piston, which moves agains
43、t the opposing force provided by the spring surrounding the piston rod. is movement is applied via a delicate linkage to the pencil, so that the amount of pencil de ection is proportional to the cylinder pressure. e rotating drum is spring-loaded in a rest position. e drum base is fastened to a cord
44、 that wraps around it. is cord exits the device via a guide pulley and is ultimately attached to the cranksha at a suitable point. Once the cord is attached and tensioned correctly, rotational movement of the crank will apply a cyclic tensioning of the cord, which rotates the drum, and then releases
45、 it. e drum position thus has a direct relationship with the crank position and hence the piston position and cylinder volume. With engine operation, and the proper setup, this allows the two measured parameters of cylinder pressure and crank position (i.e., volume) to be drawn and plotted against e
46、ach other at the drum surface. e drum is normally loaded with a sheet of paper, held in place with small steel ngers. A er a measurement, the recorded curve can be removed from the instrument for analysis and further calculations. A typical indicator diagram from such a device is shown in Figure 1.4
47、. e spring in the measuring cylinder (opposing the force from the cylinder pressure) is interchangeable, allowing the unit to be used on engines of varying applications (depending Figure 1.3 A drum-type steam engine indicator. (Source: ) R388_EngineCombustion_Text.indb 4 R388_EngineCombustion_Text.i
48、ndb 4 6/23/10 12:06:37 PM 6/23/10 12:06:37 PM 5 Early Engine Indicators | Chapter 1 on the peak pressure of the engine). Numerous indicator designs were developed to overcome inherent problems associated with measurement, such as pressure oscillations and adaptations to engines with di erent degrees
49、 of crank throw. Although these simple mechanical devices were developed for steam engine applications, as internal combustion engines became more common in the marketplace, the same technology was applied to these engines to assist the engineer in understanding the in-cylinder energy transfer process. A notable development was the Ric