Fluid Mechanics: Fundamentals and Applications 4th Edition

Book Preface

BACKGROUND

Fluid mechanics is an exciting and fascinating subject with unlimited practical applications ranging from microscopic biological systems to automobiles, airplanes, and spacecraft propulsion. Fluid mechanics has also historically been one of the most challenging subjects for undergraduate students because proper analysis of fluid mechanics problems requires not only knowledge of the concepts but also physical intuition and experience. Our hope is that this book, through its careful explanations of concepts and its use of numerous practical examples, sketches, figures, and photographs, bridges the gap between knowledge and the proper application of that knowledge.

Fluid mechanics is a mature subject; the basic equations and approximations are well established and can be found in any introductory textbook. Our book is distinguished from other introductory books because we present the subject in a progressive order from simple to more difficult, building each chapter upon foundations laid down in earlier chapters. We provide more diagrams and photographs than other books because fluid mechanics is, by its nature, a highly visual subject. Only by illustrating the concepts discussed, can students fully appreciate the mathematical significance of the material.

OBJECTIVES

This book has been written for the first fluid mechanics course for undergraduate engineering students. There is sufficient material for a two-course sequence, if desired. We assume that readers will have an adequate background in calculus, physics, engineering mechanics, and thermodynamics.

The objectives of this text are
⬤⬤ To present the basic principles and equations of fluid mechanics.
⬤⬤ To show numerous and diverse real-world engineering examples to give the student the intuition necessary for correct application of fluid mechanics principles in engineering applications.
⬤⬤ To develop an intuitive understanding of fluid mechanics by emphasizing the physics, and reinforcing that understanding through illustrative figures and photographs.

The book contains enough material to allow considerable flexibility in teaching the course. Aeronautics and aerospace engineers might emphasize potential flow, drag and lift, compressible flow, turbomachinery, and CFD, while mechanical or civil engineering instructors might choose to emphasize pipe flows and open-channel flows, respectively.

NEW TO THE FOURTH EDITION

All the popular features of the previous editions have been retained while new ones have been added. The main body of the text remains largely unchanged. A noticeable change is the addition of a number of exciting new pictures throughout the book.

Four new subsections have been added: “Uniform versus Nonuniform Flow” and “Equation Solvers” to Chap. 1, “Flying in Nature” by guest author Azar Eslam Panah of Penn State Berks to Chap. 11, and “CFD Methods for Two-Phase Flows” by guest author Alex Rattner of Penn State to Chap. 15. In Chap. 8, we now highlight the explicit Churchill equation as an alternative to the implicit Colebrook equation.

Two new Application Spotlights, have been added: “Smelling Food; the Human Airway” by Rui Ni of Penn State, to Chap. 4, and “Multicolor Particle Shadow Velocimetry/Accelerometry” by Michael McPhail and Michael Krane of Penn State to Chap. 8.

A large number of the end-of-chapter problems in the text have been modified and many problems were replaced by new ones. Also, several of the solved example problems have been replaced.

PHILOSOPHY AND GOAL

The Fourth Edition of Fluid Mechanics: Fundamentals and Applications has the same goals and philosophy as the other texts by lead author Yunus Çengel.
⬤⬤ Communicates directly with tomorrow’s engineers in a simple yet precise manner
⬤⬤ Leads students toward a clear understanding and firm grasp of the basic principles of fluid mechanics
⬤⬤ Encourages creative thinking and development of a deeper understanding and intuitive feel for fluid mechanics
⬤⬤ Is read by students with interest and enthusiasm rather than merely as a guide to solve homework problems

The best way to learn is by practice. Special effort is made throughout the book to reinforce the material that was presented earlier (in each chapter as well as in material from previous chapters). Many of the illustrated example problems and end-of-chapter problems are comprehensive and encourage students to review and revisit concepts and intuitions gained previously.

Throughout the book, we show examples generated by computational fluid dynamics (CFD). We also provide an introductory chapter on the subject. Our goal is not to teach the details about numerical algorithms associated with CFD—this is more properly presented in a separate course. Rather, our intent is to introduce undergraduate students to the capabilities and limitations of CFD as an engineering tool. We use CFD solutions in much the same way as experimental results are used from wind tunnel tests (i.e., to reinforce understanding of the physics of fluid flows and to provide quality flow visualizations that help explain fluid behavior). With dozens of CFD end-of-chapter problems posted on the website, instructors have ample opportunity to introduce the basics of CFD throughout the course.