Introduction to Compressible Fluid Flow, Second Edition, 2nd Edition

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Preface

Compressible ow occurs in many devices encountered in mechanical and aerospace

engineering practice, and knowledge of the effects of compressibility on a ow is therefore

required by many professional mechanical and aerospace engineers. Most conventional

course sequences in uid mechanics and thermodynamics deal with some aspects of

compressible uid ow, but the treatment is usually relatively supercial. For this reason,

many mechanical and aerospace engineering schools offer a course dealing with com-

pressible uid ow at the senior undergraduate or at the graduate level. The purpose of

such courses is to expand and extend the coverage given in previous uid mechanics and

thermodynamics courses. This book is intended to provide the background material for

such courses. This book also lays the foundation for more advanced courses on specialized

aspects of the subject such as hypersonic ow, thus complementing the more advanced

books in this area.

The widespread use of computer software for the analysis of engineering problems has,

in many ways, increased the need to understand the assumptions and the theory on which

such analyses are based. Such an understanding is required to interpret the computed

results and to judge whether a particular piece of software will give results that are of

adequate accuracy for the application being considered. Therefore, while numerical solu-

tions are discussed in Appendix B of this book, the major emphasis is on developing an

understanding of the material and of the assumptions conventionally conventionally used

in analyzing compressible uid ows. Compared with available textbooks on the subject,

then, this book is, it is hoped, distinguished by its attempt to develop a thorough under-

standing of the theory and of the assumptions on which this theory is based, by its attempt

to develop in the student a fascination with the phenomena involved in compressible ow,

and by the breadth of its coverage.

Our goal in writing this new text was to provide students with a clear explanation of

the physical phenomena encountered in compressible ow, to develop in them an aware-

ness of practical situations in which compressibility effects are likely to be important, to

provide a thorough explanation of the assumptions conventionally used in the analysis

of compressible ows, to provide a broad coverage of the subject, and to provide a rm

foundation for the study of more advanced and specialized aspects of the subject. We have

also tried to adopt an approach that will develop in the student a fascination with the phe-

nomena involved in compressible ow.

The rst seven chapters of this book deal with the fundamental aspects of the subject.

They review some background material and discuss the analysis of isentropic ows, of nor-

mal and oblique shock waves, and of expansion waves. The next three chapters discuss the

application of this material to the study of nozzle characteristics, of friction effects, and of

heat exchange effects. Chapters dealing with the analysis of generalized one-dimensional

ow, with simple numerical methods, and with two-dimensional ows are then given. The

last three chapters in this book are interrelated and provide an introduction to hypersonic

ow, to high-temperature gas effects, and to low-density ows. Some discussion of experi-

mental methods is incorporated into this book, mainly to illustrate the theoretical material

being discussed. However, because a number of shadowgraph and Schlieren photographs

are given in the text, a separate discussion of these and other related methods of ow visu-

alization is provided in Appendix D.