AppliedFluidMechanicsSixth Edition

Robert L. MottUniversity of Dayton

PEARSON

Prentkv

Pearson Education International

Contents

CHAPTER 1THE NATURE OF FLUIDS AND THE STUDYOF FLUID MECHANICS

1.1 The Big Picture 11.2 Objectives 31.3 Basic Introductory Concepts 31.4 The International System of Units (SI) 41.5 The U.S. Customary System 51.6 Weight and Mass 61.7 Temperature 81.8 Consistent Units in an Equation 91.9 The Definition of Pressure 111.10 Compressibility 131.11 Density, Specific Weight, and Specific Gravity 141.12 Surface Tension 19

References 21Internet Sites 21Practice Problems 21Computer Programming Assignments 24

CHAPTER 2VISCOSITY OF FLUIDS , 26

2.1 The Big Picture 262.2 Objectives 262.3 Dynamic Viscosity 272.4 Kinematic Viscosity 292.5 Newtonian Fluids and Non-Newtonian Fluids 302.6 Variation of Viscosity with Temperature 332.7 Viscosity Measurement 352.8 SAE Viscosity Grades 442.9 ISO Viscosity Grades 462.10 Hydraulic Fluids for Fluid Power Systems 46

References 48Internet Sites 48Practice Problems 49Computer Programming Assignments 51

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CHAPTER 3PRESSURE MEASUREMENT 52

3.1 The Big Picture 523.2 Objectives 523.3 Absolute and Gage Pressure 533.4 Relationship between Pressure and Elevation 553.5 Development of the Pressure-Elevation Relation 573.6 Pascal's Paradox 613.7 Manometers 623.8 Barometers 673.9 Pressure Expressed as the Height of a Column of Liquid 693.10 Pressure Gages and Transducers 70

References 74Internet Sites 75Practice Problems 75

CHAPTER 4FORCES DUE TO STATIC FLUIDS 83

4.1 The Big Picture 834.2 Objectives 854.3 Gases under Pressure 854.4 Horizontal Flat Surfaces under Liquids 864.5 Rectangular Walls 874.6 Submerged Plane Areas—General 904.7 Development of the General Procedure for Forces on Submerged

Plane Areas 944.8 Piezometric Head 964.9 Distribution of Force on a Submerged Curved Surface 974.10 Effect of a Pressure above the Ruid Surface 1034.11 Forces on a Curved Surface with Ruid Below It 1034.12 Forces on Curved Surfaces with Ruid Above and Below 104

Practice Problems 105Computer Programming Assignments 122,

CHAPTER 5BUOYANCY AND STABILITY 123

5.1 The Big Picture 1235.2 Objectives 1245.3 Buoyancy 1245.4 Buoyancy Materials 1325.5 Stability of Completely Submerged Bodies 1335.6 Stability of Floating Bodies 1355.7 Degree of Stability 140

Reference 142Internet Sites 142Practice Problems 142Computer Programming Assignments 152

Contents ix

CHAPTER 6FLOW OF FLUIDS AND BERNOULLI'S EQUATION 153

6.1 The Big Picture 1536.2 Objectives 1546.3 Fluid Row Rate and the Continuity Equation 1546.4 Commercially Available Pipe and Tubing 1586.5 Recommended Velocity of Flow in Pipe and Tubing 1616.6 Conservation of Energy—Bernoulli's Equation 1656.7 Interpretation of Bernoulli's Equation 1676.8 Restrictions on Bernoulli's Equation 1696.9 Applications of Bernoulli's Equation 1696.10 Torricelli's Theorem 1796.11 Flow Due to a Falling Head 182

References 185Internet Sites 185Practice Problems 186Computer Programming Assignments 196

CHAPTER 7GENERAL ENERGY EQUATION 197

7.1 The Big Picture 1977.2 Objectives 1997.3 Energy Losses and Additions 1997.4 Nomenclature of Energy Losses and Additions 2027.5 General Energy Equation 2027.6 Power Required by Pumps 2077.7 Power Delivered to Fluid Motors 211

Practice Problems 213

CHAPTER 8REYNOLDS NUMBER, LAMINAR FLOW, TURBULENTFLOW, AND ENERGY LOSSES DUE TO FRICTION 226

8.1 The Big Picture 2268.2 Objectives 2298.3 Reynolds Number 2308.4 Critical Reynolds Numbers 2318.5 Darcy's Equation 2338.6 Friction Loss in Laminar Flow 2338.7 Friction Loss in Turbulent Flow 2358.8 Equations for the Friction Factor 2428.9 Hazen-Williams Formula for Water Flow 2438.10 Other Forms of the Hazen-Williams Formula 2458.11 Nomograph for Solving the Hazen-Williams Formula 245

References 247Internet Sites 247Practice Problems 247Computer Programming Assignments 254

Contents

CHAPTER 9VELOCITY PROFILES FOR CIRCULAR SECTIONSAND FLOW IN NONCIRCULAR SECTIONS 255

9.1 The Big Picture 2559.2 Objectives 2569.3 Velocity Profiles 2569.4 Velocity Profile for Laminar Row 2579.5 Velocity Profile for Turbulent Flow 2589.6 Flow in Noncircular Sections 2609.7 Computational Fluid Dynamics 266

References 268Internet Sites 268Practice Problems 268Computer Programming Assignments 277

CHAPTER 10MINOR LOSSES 278

10.1 The Big Picture 27810.2 Objectives 28010.3 Resistance Coefficient 28110.4 Sudden Enlargement 28110.5 Exit Loss 28410.6 Gradual Enlargement 28610.7 Sudden Contraction 28810.8 Gradual Contraction 29010.9 Entrance Loss 29210.10 Resistance Coefficients for Valves and Fittings 29310.11 Application of Standard Valves 30010.12 Pipe Bends 30310.13 Pressure Drop in Ruid Power Valves 30510.14 Flow Coefficients for Valves Using Cy 31010.15 Plastic Valves 311

References 313Internet Sites 313Practice Problems 314Computer-Aided Analysis and Design Assignments 319

CHAPTER 11SERIES PIPELINE SYSTEMS 320

11.1 The Big Picture 32011.2 Objectives 32111.3 Class I Systems 32111.4 Spreadsheet Aid for Class I Problems 32711.5 Class II Systems 33011.6 Class III Systems 33911.7 Pipeline Design for Structural Integrity 343

References 345

Contents xi

Internet Sites 346Practice Problems 346Computer-Aided Analysis and Design Assignments 357

CHAPTER 12

PARALLEL PIPELINE SYSTEMS 358

12.1 The Big Picture 35812.2 Objectives 36012.3 Systems with Two Branches 36112.4 Systems with Three or More Branches—Networks 368

Reference 377Internet Sites 377Practice Problems 377Computer Programming Assignments 381

CHAPTER 13

PUMP SELECTION AND APPLICATION 382

13.1 The Big Picture 38213.2 Objectives 38413.3 Parameters Involved in Pump Selection 38513.4 Types of Pumps 38513.5 Positive-Displacement Pumps 38513.6 Kinetic Pumps 39213.7 Performance Data for Centrifugal Pumps 39813.8 Affinity Laws for Centrifugal Pumps 40013.9 Manufacturers' Data for Centrifugal Pumps 40113.10 The Operating Point of a Pump and Pump Selection 41013.11 Net Positive Suction Head 41113.12 Suction Line Details 41713.13 Discharge Line Details 41813.14 Piping System Design and Pump Selection Procedure 41913.15 Alternate System Operating Modes 42313.16 Pump Selection and Specific Speed 42913.17 Life Cycle Costs for Pumped Fluid Systems 43013.18 Software for Piping System Design and Pump Selection 433

References 434Internet Sites 434Software for Piping System Design 435Practice Problems 436Design Problems 438Comprehensive Design Problem 441

CHAPTER 14

OPEN-CHANNEL FLOW 443

14.1 The Big Picture 44314.2 Objectives 44414.3 Classification of Open-Channel Flow 445

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14.4 Hydraulic Radius and Reynolds Number in Open-ChannelFlow 446

14.5 Kinds of Open-Channel Flow 44714.6 Uniform Steady Flow in Open Channels 44814.7 The Geometry of Typical Open Channels 45314.8 The Most Efficient Shapes for Open Channels 45614.9 Critical Row and Specific Energy 45714.10 Hydraulic Jump 45914.11 Open-Channel Flow Measurement 462

References 467Internet Sites 467Practice Problems 468Computer Programming Assignments 471

CHAPTER 15FLOW MEASUREMENT 473

15.1 The Big Picture 47315.2 Objectives 47415.3 Rowmeter Selection Factors 47415.4 Variable-Head Meters 47615.5 Variable-Area Meters 48515.6 Turbine Flowmeter 48615.7 Vortex Flowmeter 48715.8 Magnetic Rowmeter 48715.9 Ultrasonic Flowmeters 48915.10 Positive Displacement Meters 48915.11 Mass Row Measurement 49015.12 Velocity Probes 49215.13 Level Measurement 49715.14 Computer-Based Data Acquisition and Processing 499

References 499Internet Sites 499Review Questions 500Practice Problems 501 .Computer Programming Assignments 502

CHAPTER 16FORCES DUE TO FLUIDS IN MOTION 503

16.1 The Big Picture 50316.2 Objectives 50416.3 Force Equation 50416.4 Impulse-Momentum Equation 50516.5 Problem-Solving Method Using the Force Equations 50516.6 Forces on Stationary Objects 50616.7 Forces on Bends in Pipelines 50916.8 Forces on Moving Objects 513

Practice Problems 514

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CHAPTER 17DRAG AND LIFT 520

17.1 The Big Picture 52017.2 Objectives 52117.3 Drag Force Equation 52217.4 Pressure Drag 52317.5 Drag Coefficient 52417.6 Friction Drag on Spheres in Laminar Flow 53017.7 Vehicle Drag 53117.8 Compressibility Effects and Cavitation 53317.9 Lift and Drag on Airfoils 534

References 537Internet Sites 537Practice Problems 537

CHAPTER 18

FANS, BLOWERS, COMPRESSORS, ANDTHE FLOW OF GASES 542

18.1 The Big Picture 54218.2 Objectives 54318.3 Gas Flow Rates and Pressures 54318.4 Classification of Fans, Blowers, and Compressors 54418.5 Flow of Compressed Air and Other Gases in Pipes 54918.6 Flow of Air and Other Gases through Nozzles 556

References 564Internet Sites 564Practice Problems 565Computer Programming Assignments 567

CHAPTER 19

FLOW OF AIR IN DUCTS 568

19.1 The Big Picture 56819.2 Objectives 57019.3 Energy Losses in Ducts 57019.4 Duct Design 57619.5 Energy Efficiency and Practical Considerations

in Duct Design 583References 584Internet Sites 584Practice Problems 585

APPENDIXES 589

A Properties of Water 589B Properties of Common Liquids 591C Typical Properties of Petroleum Lubricating Oils 593

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D Variation of Viscosity with Temperature 594E Properties of Air 597F Dimensions of Steel Pipe 601G Dimensions of Steel Tubing 603H Dimensions of Type K Copper Tubing 604I Dimensions of Ductile Iron Pipe 605J Areas of Circles 606K Conversion Factors 608L Properties of Areas 611M Properties of Solids 613N Gas Constant, Adiabatic Exponent, and Critical Pressure Ratio for

Selected Gases 615

ANSWERS TO SELECTED PROBLEMS 616INDEX 623