Gas Turbine Engineering Handbook Meherwan P Boyce.pdf
Clarence Causley
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The use of gas turbines in the petrochemical, power generation, and offshore industries has mushroomed in the past few years. The power industry in the past 10 years has embraced the combined cycle power plants, and the new high-efficiency gas turbines are at the center of this growth segment of the industry. However, owing to the spiraling costs of natural gas, many of these plants designed for base load service have been cycled on a daily basis from part loads of 50% to full load, and in many cases, have had to be shutdown at weekends. The new maintenance chapters, with their case histories, should be of great assistance to the engineers in the field who have to operate their plant at other than design conditions of base loaded operation. Investigation into operation of these plants on other fuels is also covered in this edition.
In the first chapter, nearly 90 pages are devoted to the history of gas turbines and the details in the advancement in many of the major components in gas turbines. It is a summary of the major components in a gas turbine and their development over the years.
This edition also provides the basic fluid mechanics and thermodynamics for the young engineering graduate or undergraduate student who is being exposed to the field of turbomachinery for the first time. This book is very useful as a textbook for undergraduate or graduate turbomachinery courses as well as for in-house company training programs related to the petrochemical, power generation, and offshore industries. The fourth edition is not only an update of this technology in gas turbines but also provides a clearer understanding of the basic thermodynamics, cycles, and fluid mechanic relationships of turbines, as outlined in Chapters 2 and 3 based on the comments from many of the students who have used this book at the undergraduate level. These chapters with new figures and relationships have made it easier to understand the complex thermodynamics and fluid mechanic relationships, and also the new cycles, which have been introduced.
In this edition, chapters have been totally rewritten in the areas of combustors, axial and radial turbine expanders, and gear systems. The new chapter on combustors deals with the combustion problems with DLN combustors and the problems associated with these combustors such as flashback problems. The emphasis on low NOx emissions from gas turbines has led to the development of a new breed of Dry Low NOx combustors, and their problems are dealt with in detail in this edition.
Hot gas turbine expanders, both axial and radial, have been dealt with in great detail in this edition. The new expanded chapter on radial turbines gives the reader much more insights into the design of these radial gas expanders and radial turbines. These turbines are getting more important as plant gases are being used to power turbines in refineries and other chemical plants.
The author thanks Ms. Lisa Ford, Director of Engineering, Power Transmission Division, Lufkin Industries Inc., who helped to rewrite this chapter so that the readers are exposed to the latest in gear technology as used in gas turbines. Detailed descriptions of the tools that make these gears and the gear characteristics are given in this expanded chapter.
This book deals with case histories of gas turbines from deterioration of the performance of gas turbines to failures encountered in all the major components of the gas turbine. The chapter on Maintenance Techniques has been completely rewritten and updated. These chapters deal with Long-Term Service Agreements (LTSAs), which have become the major service agreements for new advanced gas turbines, as lending institutions have more faith in the original equipment manufacturer for dealing with problems. Special maintenance tables have been added, so that the reader can troubleshoot problems on gas turbines they may encounter in the field.
The new advanced gas turbines have firing temperatures of 2600 F (1427 C) and pressure ratios exceeding 40:1 in aircraft gas turbines and over 30:1 in industrial turbines. This has led to the enhancement of axial flow compressor design; to fully understand the operating mechanics of these high-pressure-ratio axial-flow compressors, the reader must carefully read Chapter 7. The chapter covers in detail the advent of surge and describes in great detail the different mechanisms of surge, rotating stall, and choke flow conditions in the compressor of gas turbines.
Advances in materials and coatings have spurred the technology of compressor and turbine design, and the new editions have treated this new area in great detail. The last two editions have dealt with an upgrade in the design and maintenance of advanced gas turbines and with most of the applicable codes in the area of both performance and mechanical standards.
The last two new editions have been written with the experienced engineer in mind who is working in power plants and in petrochemical and offshore installations. These two editions should help him or her to understand more clearly problems encountered in the field and how to prevent them.
This new edition will give the manufacturer a glimpse of some of the problems associated with gas turbines in the field and help users to achieve maximum performance efficiency and high availability of their gas turbines.
I have been involved in the research, design, operation, and maintenance of gas turbines since the early 1960s. I have had the privilege of teaching courses at the graduate and undergraduate levels at the University of Oklahoma and Texas A&M University, and have lectured at universities in the United Kingdom, Japan, and India, and now, in general, in the industry. There have been over 4500 students through my courses, designed for the engineer in the field, representing over 520 companies from around the world. They have used the book, and their comments and my field troubleshooting experiences have been very influential in the updating of material in these four editions. The enthusiasm of the students associated with these courses gave me the inspiration to undertake this endeavor. The many courses I have taught over the past 40 years have been an educational experience for me, and, I hope, have been satisfying for my students. The discussions that resulted from my association as a consultant to the power, petrochemical, and aviation industries with highly professional individuals have been a major contribution to both my personal and professional life as well as to this new edition of the book. In this edition, I have tried to assimilate the subject matter of various papers (and sometimes diverse views) into a comprehensive, unified treatment of gas turbines. Many illustrations, curves, and tables are employed to broaden the understanding of the descriptive text. I have provided extensive new charts that can be used to diagnose problems. In addition, the references direct the reader to sources of information that will help to investigate and solve specific problems. I hope that this book will serve as a reference text after it has accomplished its primary objective of introducing the reader to the broad subject of gas turbines.
I thank the many engineers whose published work and discussions I have had the privilege of using in the book, and whose articles make a cornerstone to this work. The Turbomachinery Symposium, which I have had the distinct honor of founding and chairing for eight years, and the proceedings of the Symposium have contributed many interesting technology issues from a design and maintenance point of view to this book. Special thanks to my colleagues on the Advisory Committee of the Texas A&M University Turbomachinery Symposium, of which I have been a member for 40 years, and to Dr. Dara Childs, who is now the chairman of the Advisory Committee.
I sincerely hope that my readers from all over the world, who have made this the most read book in the field over the past 35 years, find this new edition as interesting as the past three editions. I hope that my 50 years of experience in the field will be beneficial to all who read this book.
The new advanced gas turbines have firing temperatures of 2600 F (1427 C), and pressure ratios exceeding 40:1 in aircraft gas turbines, and over 30:1 in industrial turbines. This has led to the rewriting of Chapter 7, to fully understand the operating mechanics of these high pressure ratio axial-flow compressors. The chapter covers in detail the advent of surge, and describes in great detail the different mechanisms of surge, rotating stall, and choke flow conditions in the compressor of the gas turbine. Advances in materials and coatings have spurred this technology, and the new edition has treated this new area in great detail. The emphasis on low NOx emissions from gas turbines has led to the development of a new breed of Dry Low NOx combustors, and their problems are dealt with in depth in this new edition. The third edition deals with an upgrade in the design and maintenance of advanced gas turbines and deals with most of the applicable codes both in the area of performance and mechanical standards.
The new edition has been written with the experienced engineer in mind who is working in power plants, and in petrochemical and offshore installations. This edition should help him or her understand more clearly problems encountered in the field, and how to prevent them.
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