cen72367_fm.qxd 11/23/04 11:22 AM Page i FLUID MECHANICS FUNDAMENTALS AND APPLICATIONS cen72367_fm.qxd 11/23/04 11:22 AM Page ii McGRAW-HILL SERIES IN MECHANICAL ENGINEERING Alciatore and Histand: Anderson: Anderson: Anderson: Anderson: Barber: Beer/Johnston: Beer/Johnston/DeWolf: Borman and Ragland: Budynas: Çengel and Boles: Çengel and Cimbala: Çengel and Turner: Çengel: Crespo da Silva: Dieter: Dieter: Doebelin: Dunn: EDS, Inc.: Hamrock/Jacobson/Schmid: Henkel and Pense: Heywood: Holman: Holman: Hsu: Hutton: Kays/Crawford/Weigand: Kelly: Kreider/Rabl/Curtiss: Mattingly: Meirovitch: Norton: Palm: Reddy: Ribando: Schaffer et al.: Schey: Schlichting: Shames: Shigley/Mischke/Budynas: Smith: Stoecker: Suryanarayana and Arici: Turns: Ugural: Ugural: Ullman: Wark and Richards: White: White: Zeid: Introduction to Mechatronics and Measurement Systems Computational Fluid Dynamics: The Basics with Applications Fundamentals of Aerodynamics Introduction to Flight Modern Compressible Flow Intermediate Mechanics of Materials Vector Mechanics for Engineers Mechanics of Materials Combustion Engineering Advanced Strength and Applied Stress Analysis Thermodynamics: An Engineering Approach Fluid Mechanics: Fundamentals and Applications Fundamentals of Thermal-Fluid Sciences Heat Transfer: A Practical Approach Intermediate Dynamics Engineering Design: A Materials & Processing Approach Mechanical Metallurgy Measurement Systems: Application & Design Measurement & Data Analysis for Engineering & Science I-DEAS Student Guide Fundamentals of Machine Elements Structure and Properties of Engineering Material Internal Combustion Engine Fundamentals Experimental Methods for Engineers Heat Transfer MEMS & Microsystems: Manufacture & Design Fundamentals of Finite Element Analysis Convective Heat and Mass Transfer Fundamentals of Mechanical Vibrations The Heating and Cooling of Buildings Elements of Gas Turbine Propulsion Fundamentals of Vibrations Design of Machinery System Dynamics An Introduction to Finite Element Method Heat Transfer Tools The Science and Design of Engineering Materials Introduction to Manufacturing Processes Boundary-Layer Theory Mechanics of Fluids Mechanical Engineering Design Foundations of Materials Science and Engineering Design of Thermal Systems Design and Simulation of Thermal Systems An Introduction to Combustion: Concepts and Applications Stresses in Plates and Shells Mechanical Design: An Integrated Approach The Mechanical Design Process Thermodynamics Fluid Mechanics Viscous Fluid Flow Mastering CAD/CAM cen72367_fm.qxd 11/23/04 11:22 AM Page iii FLUID MECHANICS FUNDAMENTALS AND APPLICATIONS YUNUS A ÇENGEL Department of Mechanical Engineering University of Nevada, Reno JOHN M CIMBALA Department of Mechanical and Nuclear Engineering The Pennsylvania State University cen72367_fm.qxd 11/23/04 11:22 AM Page iv FLUID MECHANICS: FUNDAMENTALS AND APPLICATIONS Published by McGraw-Hill, a business unit of The McGraw-Hill Companies, Inc., 1221 Avenue of the Americas, New York, NY 10020 Copyright © 2006 by The McGraw-Hill Companies, Inc All rights reserved No part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written consent of The McGraw-Hill Companies, Inc., including, but not limited to, in any network or other electronic storage or transmission, or broadcast for distance learning Some ancillaries, including electronic and print components, may not be available to customers outside the United States This book is printed on acid-free paper DOW/DOW ISBN 0–07–247236–7 Senior Sponsoring Editor: Suzanne Jeans Managing Developmental Editor: Debra D Matteson Developmental Editor: Kate Scheinman Senior Marketing Manager: Mary K Kittell Senior Project Manager: Sheila M Frank Senior Production Supervisor: Sherry L Kane Media Technology Producer: Eric A Weber Senior Designer: David W Hash (USE) Cover image: © Getty/Eric Meola, Niagara Falls Senior Photo Research Coordinator: Lori Hancock Photo Research: Judy Ladendorf/The Permissions Group Supplemental Producer: Brenda A Ernzen Compositor: Lachina Publishing Services Typeface: 10.5/12 Times Roman Printer: R R Donnelley Willard, OH Library of Congress Cataloging-in-Publication Data Çengel, Yunus A Fluid mechanics : fundamentals and applications / Yunus A Çengel, John M Cimbala.—1st ed p cm.—(McGraw-Hill series in mechanical engineering) ISBN 0–07–247236–7 Fluid dynamics I Cimbala, John M II Title III Series TA357.C43 2006 620.1'06—dc22 www.mhhe.com 2004058767 CIP cen72367_fm.qxd 11/23/04 11:22 AM Page v Dedication To all students—In hopes of enhancing your desire and enthusiasm to explore the inner workings of our marvelous universe, of which fluid mechanics is a small but fascinating part; our hope is that this book enhances your love of learning, not only about fluid mechanics, but about life cen72367_fm.qxd 11/23/04 11:22 AM Page vi ABOUT THE AUTHORS Yunus A Çengel is Professor Emeritus of Mechanical Engineering at the University of Nevada, Reno He received his B.S in mechanical engineering from Istanbul Technical University and his M.S and Ph.D in mechanical engineering from North Carolina State University His research areas are renewable energy, desalination, exergy analysis, heat transfer enhancement, radiation heat transfer, and energy conservation He served as the director of the Industrial Assessment Center (IAC) at the University of Nevada, Reno, from 1996 to 2000 He has led teams of engineering students to numerous manufacturing facilities in Northern Nevada and California to industrial assessments, and has prepared energy conservation, waste minimization, and productivity enhancement reports for them Dr Çengel is the coauthor of the widely adopted textbook Thermodynamics: An Engineering Approach, 4th edition (2002), published by McGraw-Hill He is also the author of the textbook Heat Transfer: A Practical Approach, 2nd edition (2003), and the coauthor of the textbook Fundamentals of ThermalFluid Sciences, 2nd edition (2005), both published by McGraw-Hill Some of his textbooks have been translated to Chinese, Japanese, Korean, Spanish, Turkish, Italian, and Greek Dr Çengel is the recipient of several outstanding teacher awards, and he has received the ASEE Meriam/Wiley Distinguished Author Award for excellence in authorship in 1992 and again in 2000 Dr Çengel is a registered Professional Engineer in the State of Nevada, and is a member of the American Society of Mechanical Engineers (ASME) and the American Society for Engineering Education (ASEE) John M Cimbala is Professor of Mechanical Engineering at The Pennsylvania State Univesity, University Park He received his B.S in Aerospace Engineering from Penn State and his M.S in Aeronautics from the California Institute of Technology (CalTech) He received his Ph.D in Aeronautics from CalTech in 1984 under the supervision of Professor Anatol Roshko, to whom he will be forever grateful His research areas include experimental and computational fluid mechanics and heat transfer, turbulence, turbulence modeling, turbomachinery, indoor air quality, and air pollution control During the academic year 1993–94, Professor Cimbala took a sabbatical leave from the University and worked at NASA Langley Research Center, where he advanced his knowledge of computational fluid dynamics (CFD) and turbulence modeling Dr Cimbala is the coauthor of the textbook Indoor Air Quality Engineering: Environmental Health and Control of Indoor Pollutants (2003), published by Marcel-Dekker, Inc He has also contributed to parts of other books, and is the author or co-author of dozens of journal and conference papers More information can be found at www.mne.psu.edu/cimbala Professor Cimbala is the recipient of several outstanding teaching awards and views his book writing as an extension of his love of teaching He is a member of the American Institute of Aeronautics and Astronautics (AIAA), the American Society of Mechanical Engineers (ASME), the American Society for Engineering Education (ASEE), and the American Physical Society (APS) cen72367_fm.qxd 11/23/04 11:22 AM Page vii BRIEF CONTENTS CHAPTER ONE INTRODUCTION AND BASIC CONCEPTS CHAPTER TWO PROPERTIES OF FLUIDS 35 CHAPTER THREE PRESSURE AND FLUID STATICS CHAPTER FOUR FLUID KINEMATICS CHAPTER 65 121 FIVE MASS, BERNOULLI, AND ENERGY EQUATIONS CHAPTER SIX MOMENTUM ANALYSIS OF FLOW SYSTEMS CHAPTER 171 227 SEVEN DIMENSIONAL ANALYSIS AND MODELING CHAPTER EIGHT FLOW IN PIPES 321 CHAPTER NINE DIFFERENTIAL ANALYSIS OF FLUID FLOW 269 399 CHAPTER TEN APPROXIMATE SOLUTIONS OF THE NAVIER–STOKES EQUATION CHAPTER ELEVEN FLOW OVER BODIES: DRAG AND LIFT 561 C H A P T E R T W E LV E COMPRESSIBLE FLOW 611 CHAPTER THIRTEEN OPEN-CHANNEL FLOW CHAPTER FOURTEEN TURBOMACHINERY CHAPTER 679 735 FIFTEEN INTRODUCTION TO COMPUTATIONAL FLUID DYNAMICS 817 471 cen72367_fm.qxd 11/23/04 11:22 AM Page viii CONTENTS Preface xv CHAPTER Application Spotlight: What Nuclear Blasts and Raindrops Have in Common 31 INTRODUCTION AND BASIC CONCEPTS 1–1 Introduction CHAPTER What Is a Fluid? Application Areas of Fluid Mechanics 1–2 1–3 1–4 The No-Slip Condition A Brief History of Fluid Mechanics Classification of Fluid Flows 2–1 2–6 2–7 1–8 44 Viscosity 46 Surface Tension and Capillary Effect 51 53 Summary 55 References and Suggested Reading 56 Application Spotlight: Cavitation 57 Problems 21 58 Problem-Solving Technique 22 Step 1: Problem Statement 22 Step 2: Schematic 23 Step 3: Assumptions and Approximations 23 Step 4: Physical Laws 23 Step 5: Properties 23 Step 6: Calculations 23 Step 7: Reasoning, Verification, and Discussion 1–9 38 Vapor Pressure and Cavitation 39 Energy and Specific Heats 41 Coefficient of Compressibility 42 Capillary Effect Mathematical Modeling of Engineering Problems 21 Modeling in Engineering Density and Specific Gravity 37 Coefficient of Volume Expansion System and Control Volume 14 Importance of Dimensions and Units 15 Some SI and English Units 16 Dimensional Homogeneity 18 Unity Conversion Ratios 20 1–7 36 Density of Ideal Gases 2–3 2–4 2–5 35 Introduction 36 Continuum 2–2 30 TWO PROPERTIES OF FLUIDS Viscous versus Inviscid Regions of Flow Internal versus External Flow 10 Compressible versus Incompressible Flow 10 Laminar versus Turbulent Flow 11 Natural (or Unforced) versus Forced Flow 11 Steady versus Unsteady Flow 11 One-, Two-, and Three-Dimensional Flows 12 1–5 1–6 Summary 30 References and Suggested Reading Problems 32 ONE CHAPTER PRESSURE AND FLUID STATICS 3–1 25 1–10 Accuracy, Precision, and Significant Digits 26 3–2 68 The Manometer 71 Other Pressure Measurement Devices 3–3 3–4 65 Pressure 66 Pressure at a Point 67 Variation of Pressure with Depth 23 Engineering Software Packages 24 Engineering Equation Solver (EES) FLUENT 26 THREE 74 The Barometer and Atmospheric Pressure 75 Introduction to Fluid Statics 78 cen72367_fm.qxd 11/23/04 11:22 AM Page ix ix CONTENTS 3–5 Hydrostatic Forces on Submerged Plane Surfaces 79 Special Case: Submerged Rectangular Plate 3–6 3–7 Summary 102 References and Suggested Reading Problems 103 CHAPTER FLUID KINEMATICS 4–1 5–1 5–2 97 103 5–3 5–4 FOUR Lagrangian and Eulerian Descriptions 122 Fundamentals of Flow Visualization 129 5–5 5–6 5–7 4–5 Summary 215 References and Suggested Reading Problems 216 Other Kinematic Descriptions 139 CHAPTER 158 SIX MOMENTUM ANALYSIS OF FLOW SYSTEMS 227 155 6–1 Application Spotlight: Fluidic Actuators 157 Summary 156 References and Suggested Reading Problems 158 216 139 The Reynolds Transport Theorem 148 Alternate Derivation of the Reynolds Transport Theorem 153 Relationship between Material Derivative and RTT Energy Analysis of Steady Flows 206 Special Case: Incompressible Flow with No Mechanical Work Devices and Negligible Friction 208 Kinetic Energy Correction Factor, a 208 Plots of Fluid Flow Data 136 Types of Motion or Deformation of Fluid Elements Vorticity and Rotationality 144 Comparison of Two Circular Flows 147 Applications of the Bernoulli Equation 194 General Energy Equation 201 Energy Transfer by Heat, Q 202 Energy Transfer by Work, W 202 Profile Plots 137 Vector Plots 137 Contour Plots 138 4–4 Mechanical Energy and Efficiency 180 The Bernoulli Equation 185 Acceleration of a Fluid Particle 186 Derivation of the Bernoulli Equation 186 Force Balance across Streamlines 188 Unsteady, Compressible Flow 189 Static, Dynamic, and Stagnation Pressures 189 Limitations on the Use of the Bernoulli Equation 190 Hydraulic Grade Line (HGL) and Energy Grade Line (EGL) 192 121 Streamlines and Streamtubes 129 Pathlines 130 Streaklines 132 Timelines 134 Refractive Flow Visualization Techniques 135 Surface Flow Visualization Techniques 136 4–3 Conservation of Mass 173 Mass and Volume Flow Rates 173 Conservation of Mass Principle 175 Moving or Deforming Control Volumes 177 Mass Balance for Steady-Flow Processes 177 Special Case: Incompressible Flow 178 Acceleration Field 124 Material Derivative 127 4–2 Introduction 172 Conservation of Mass 172 Conservation of Momentum 172 Conservation of Energy 172 92 Fluids in Rigid-Body Motion 95 Special Case 1: Fluids at Rest 96 Special Case 2: Free Fall of a Fluid Body Acceleration on a Straight Path 97 Rotation in a Cylindrical Container 99 FIVE MASS, BERNOULLI, AND ENERGY EQUATIONS 171 82 Hydrostatic Forces on Submerged Curved Surfaces 85 Buoyancy and Stability 89 Stability of Immersed and Floating Bodies 3–8 CHAPTER 6–2 6–3 Newton’s Laws and Conservation of Momentum 228 Choosing a Control Volume 229 Forces Acting on a Control Volume 230 ... i FLUID MECHANICS FUNDAMENTALS AND APPLICATIONS cen72367_fm.qxd 11/23/04 11:22 AM Page ii McGRAW-HILL SERIES IN MECHANICAL ENGINEERING Alciatore and Histand: Anderson: Anderson: Anderson: Anderson:... 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 •... Yunus A Fluid mechanics : fundamentals and applications / Yunus A Çengel, John M Cimbala. —1st ed p cm.—(McGraw-Hill series in mechanical engineering) ISBN 0–07–247236–7 Fluid dynamics I Cimbala,