Preface to 4th edition

From the first edition of A Heat Transfer Textbook in 1981, this book was meant to serve students as they set out to understand heat transfer in its many aspects. Whether the reader studies independently or in a classroom is beside the point, since learning (in either case) means formulating and surmounting one’s own questions. Where the book succeeds, it will be because students encounter a series of “Oh, now I see!” moments.

The original edition went through several printings and was followed in 1987 by more printings of a second edition—this time with a new chapter on Mass Transfer by John H. Lienhard V who had played only a minor role in John H. Lienhard IV’s first edition. After that, we each became involved in other pursuits and were unable to prepare the needed third edition. So the book went out of print.

In the late 1990s, we developed a third edition which we decided to distribute free of charge on the Internet. We obtained funding from the Dell Star Program, did major updating, and posted it in 2000 as a part of MIT’s then new OpenCourseWare initiative. In that form, the book underwent many subsequent revisions and changes as we moved to keep up-to-date with rapidly-changing technology. Indeed, the early versions of the third edition are substantially different from the last versions. By 2010, these Internet versions had a quarter million downloads by people on all seven continents and in essentially every country in the world. We also published a small number of paperback versions of the third edition through Phlogiston Press. This fourth edition is likewise being made available by Dover Publications in an affordable hard copy.

In this edition, we’ve made many additional interstitial changes to the last version of the third edition (specifically, Version 31), including corrections, updates, and various text edits. We are calling it a fourth edition to reflect ten years of accumulated revision of the third edition.

With this edition we continue offering engineering juniors, seniors, and first-year graduate students their grounding in heat transfer — in conduction, convection, radiation, phase-change, and an introduction to the kindred subject of mass transfer. We have designed the book in such a way as to accommodate differing levels according to the instructor’s use of it (or the student’s independent selections). Accordingly, each element of the subject begins simply and may be carried through to the more sophisticated material as the instructor (or the reader) chooses.

We have strived to combine clarity with unusual care to get things right and complete. We take care to deal with the implications, limitations, and meaning of the many aspects of the subject. We have also worked to connect the subject to the real world that it serves, and to develop insight into the many phenomena connected with the subject.

In the interest of grounding students in real-world issues, we begin the book with a three-chapter introduction that takes them through the essential modes of heat transfer and gives them an understanding of the function and design of heat exchangers. With that background, students find the later and more complex aspects of the subject much more meaningful.

Thus, the first three chapters provide background that is needed throughout the chapters that follow. But only the earlier parts of subsequent chapters accumulate in this way. For example, we freely use the dimensional analysis that appears early in Chapter 4. However, while the material on fin design at the end of that chapter is an important application, much used in many industries, it is not material that one has to know to continue through subsequent chapters.

These goals are much the same as we’ve pursued over the past 30 years. However, we’ve taken the occasion of this new edition as an opportunity to refocus and renew our purposes.

We owe thanks to many people. These include our colleagues and students at MIT, the University of Houston, and elsewhere who have provided suggestions, advice, and corrections; and most especially the many thousands of people worldwide who have emailed us with thanks and encouragement to continue this project.

JHL IV, University of Houston
JHL V, Massachusetts Institute of Technology
December 2010