## Thermodynamics: An Engineering Approach, Tenth Edition

By Yunus A. Cengel, Michael A. Boles, and Mehmet Kanoğlu

**Contents:**

CHAPTER ONE

INTRODUCTION AND BASIC CONCEPTS 1

1–1 Thermodynamics and Energy 2

Application Areas of Thermodynamics 3

1–2 Importance of Dimensions and Units 4

Some SI and English Units 6

Dimensional Homogeneity 8

Unity Conversion Ratios 9

1–3 Systems and Control Volumes 10

1–4 Properties of a System 12

Continuum 13

1–5 Density and Specific Gravity 13

1–6 State and Equilibrium 15

The State Postulate 15

1–7 Processes and Cycles 16

The Steady-Flow Process 17

1–8 Temperature and the Zeroth Law of

Thermodynamics 17

Temperature Scales 18

1–9 Pressure 21

Variation of Pressure with Depth 23

1–10 Pressure Measurement Devices 25

The Barometer 25

The Manometer 28

Other Pressure Measurement Devices 31

1–11 Problem-Solving Technique 32

Step 1: Problem Statement 32

Step 2: Schematic 32

Step 3: Assumptions and Approximations 33

Step 4: Physical Laws 33

Step 5: Properties 33

Step 6: Calculations 33

Step 7: Reasoning, Verification, and Discussion 33

Engineering Software Packages 34

Equation Solvers 35

A Remark on Significant Digits 36

Summary 37

References and Suggested Readings 37

Problems 38

C H A P T E R TWO

ENERGY, ENERGY TRANSFER, AND

GENERAL

ENERGY ANALYSIS 47

2–1 Introduction 48

2–2 Forms of Energy 49

Some Physical Insight to Internal Energy 51

More on Nuclear Energy 52

Mechanical Energy 53

2–3 Energy Transfer by Heat 55

Historical Background on Heat 57

2–4 Energy Transfer by Work 58

Electrical Work 60

2–5 Mechanical Forms of Work 61

Shaft Work 62

Spring Work 63

Work Done on Elastic Solid Bars 63

Work Associated with the Stretching of a Liquid Film 63

Work Done to Raise or to Accelerate a Body 64

Nonmechanical Forms of Work 65

2–6 The First Law of Thermodynamics 66

Energy Balance 67

Energy Change of a System, ΔEsystem 67

Mechanisms of Energy Transfer, Ein and Eout 68

2–7 Energy Conversion Efficiencies 73

Efficiencies of Mechanical and Electrical Devices 76

2–8 Energy and Environment 80

Ozone and Smog 81

Acid Rain 82

The Greenhouse Effect: Global Warming and Climate

Change 82

Topic of Special Interest: Mechanisms of

Heat Transfer 85

Summary 90

References and Suggested Readings 90

Problems 91

C H A P T E R T H R E E

PROPERTIES OF PURE SUBSTANCES 101

3–1 Pure Substance 102

3–2 Phases of a Pure Substance 102

3–3 Phase-Change Processes of

Pure Substances 103

Compressed Liquid and Saturated Liquid 103

Saturated Vapor and Superheated Vapor 104

Saturation Temperature and Saturation Pressure 104

Some Consequences of Tsat and Psat Dependence 106

3–4 Property Diagrams for Phase-Change

Processes 107

1 The T-v Diagram 108

2 The P-v Diagram 109

Extending the Diagrams to Include the Solid Phase 110

3 The P-T Diagram 111

The P-v-T Surface 112

3–5 Property Tables 113

Enthalpy—A Combination Property 113

1a Saturated Liquid and Saturated Vapor States 114

1b Saturated Liquid–Vapor Mixture 115

2 Superheated Vapor 118

3 Compressed Liquid 120

Reference State and Reference Values 121

3–6 The Ideal-Gas Equation of State 124

Is Water Vapor an Ideal Gas? 126

3–7 Compressibility Factor—A Measure

of Deviation

from Ideal-

Gas Behavior 127

3–8 Other Equations of State 131

van der Waals Equation of State 131

Beattie-Bridgeman Equation of State 132

Benedict-Webb-Rubin Equation of State 132

Virial Equation of State 133

Topic of Special Interest: Vapor Pressure and Phase

Equilibrium 135

Summary 139

References and Suggested Readings 139

Problems 140

C H A P T E R F O U R

ENERGY ANALYSIS OF CLOSED

SYSTEMS 149

4–1 Moving Boundary Work 150

Polytropic Process 153

4–2 Energy Balance for Closed Systems 155

Constant-Pressure Processes of Closed Systems 157

4–3 Specific Heats 160

4–4 Internal Energy, Enthalpy, and Specific Heats of

Ideal Gases 162

Specific Heat Relations of Ideal Gases 165

4–5 Internal Energy, Enthalpy, and Specific Heats of

Solids and Liquids 170

Internal Energy Changes 170

Enthalpy Changes 171

Topic of Special Interest: Thermodynamic Aspects of Biological

Systems 174

Summary 180

References and Suggested Readings 181

Problems 182

C H A P T E R F I V E

MASS AND ENERGY ANALYSIS OFCONTROL

VOLUMES 197

5–1 Conservation of Mass 198

Mass and Volume Flow Rates 198

Conservation of Mass Principle 199

Mass Balance for Steady-Flow Processes 201

Special Case: Incompressible Flow 202

5–2 Flow Work and the Energy of a Flowing

Fluid 204

Total Energy of a Flowing Fluid 205

Energy Transport by Mass 206

5–3 Energy Analysis of Steady-Flow Systems 208

5–4 Some Steady-Flow Engineering Devices 211

1 Nozzles and Diffusers 212

2 Turbines and Compressors 215

3 Throttling Valves 217

4a Mixing Chambers 218

4b Heat Exchangers 220

5 Pipe and Duct Flow 222

5–5 Energy Analysis of Unsteady-

Flow

Processes 224

Summary 230

References and Suggested Readings 231

Problems 231

C H A P T E R S I X

THE SECOND LAW OF

THERMODYNAMICS 251

6–1 Introduction to the Second Law 252

6–2 Thermal Energy Reservoirs 253

6–3 Heat Engines 254

Thermal Efficiency 256

Can We Save Qout? 257

The Second Law of Thermodynamics: Kelvin–Planck

Statement 259

6–4 Refrigerators and Heat Pumps 260

Coefficient of Performance 261

Heat Pumps 262

Performance of Refrigerators, Air Conditioners, and Heat

Pumps 262

The Second Law of Thermodynamics: Clausius

Statement 264

Equivalence of the Two Statements 264

6–5 Perpetual-Motion Machines 266

6–6 Reversible and Irreversible Processes 268

Irreversibilities 269

Internally and Externally Reversible Processes 270

6–7 The Carnot Cycle 271

The Reversed Carnot Cycle 273

6–8 The Carnot Principles 273

6–9 The Thermodynamic Temperature Scale 275

6–10 The Carnot Heat Engine 277

The Quality of Energy 278

Quantity versus Quality in Daily Life 279

6–11 The Carnot Refrigerator and Heat Pump 280

Topic of Special Interest: Household Refrigerators 284

Summary 287

References and Suggested Readings 288

Problems 288

C H A P T E R S E V E N

ENTROPY 301

7–1 Clausius Inequalıty and Entropy 302

A Special Case: Internally Reversible Isothermal Heat Transfer

Processes 304

7–2 Entropy Generation and the Increase of Entropy

Principle 305

Some Remarks About Entropy 307

7–3 Entropy Change of Pure Substances 309

7–4 Isentropic Processes 312

7–5 Property Diagrams Involving Entropy 314

7–6 What Is Entropy? 316

The Concept of Entropy in Daily Life 318

7–7 Differential Entropy Change Relations 319

7–8 Entropy Change of Liquids and Solids 321

7–9 The Entropy Change of Ideal Gases 324

Constant Specific Heats (Approximate Analysis) 324

Variable Specific Heats (Exact Analysis) 325

Isentropic Processes of Ideal Gases 327

Summary 331

References and Suggested Readings 332

Problems 332

C H A P T E R E I G H T

ENTROPY ANALYSIS 343

8–1 Reversible Steady-Flow Work 344

Proof that Steady-Flow Devices Deliver the Most and

Consume the Least Work When the Process Is

Reversible 346

8–2 Minimizing the Compressor Work 348

Multistage Compression with Intercooling 349

8–3 Isentropic Efficiencies of Steady-Flow

Devices 351

Isentropic Efficiency of Turbines 352

Isentropic Efficiencies of Compressors and Pumps 353

Isentropic Efficiency of Nozzles 355

8–4 Entropy Balance 357

Entropy Change of a System, ΔSsystem 358

Mechanisms of Entropy Transfer, Sin and Sout 358

Entropy Generation, Sgen 360

8–5 Entropy Balance for Closed Systems 361

Entropy Generation Associated with a Heat

Transfer Process 365

8–6 Entropy Balance for Control Volumes 366

Topic of Special Interest: Reducing the Cost of

Compressed Air 369

Summary 377

References and Suggested Readings 378

Problems 378

C H A P T E R N I N E

EXERGY 391

9–1 Exergy: Work Potential of Energy 392

Exergy (Work Potential) Associated with Kinetic and Potential

Energy 393

9–2 Reversible Work and Irreversibility 395

9–3 Second-Law Efficiency 399

9–4 Exergy Change of a System 403

Exergy of a Fixed Mass: Nonflow (or Closed System)

Exergy 403

Exergy of a Flow Stream: Flow (or Stream) Exergy 405

9–5 Exergy Transfer by Heat, Work, and Mass 409

Exergy Transfer by Heat, Q 409

Exergy Transfer by Work, W 410

Exergy Transfer by Mass, m 410

9–6 The Decrease of Exergy Principle and Exergy

Destruction 411

Exergy Destruction 412

9–7 Exergy Balance: Closed Systems 413

9–8 Exergy Balance: Control Volumes 424

Exergy Balance for Steady-Flow Systems 425

Reversible Work 425

Second-Law Efficiency of Steady-Flow Devices 426

Topic of Special Interest: Implications of the Second-Law

Concepts in Daily Life 431

Summary 434

References and Suggested Readings 435

Problems 435

C H A P T E R T E N

GAS POWER CYCLES 449

10–1 Basic Considerations in the Analysis

of Power Cycles 450

10–2 The Carnot Cycle and Its Value

in Engineering 452

10–3 Air-Standard Assumptions 454

10–4 An Overview of Reciprocating Engines 455

10–5 Otto Cycle: The Ideal Cycle for Spark-Ignition

Engines 457

10–6 Diesel Cycle: The Ideal Cycle for

Compression-

Ignition Engines 463

10–7 Stirling and Ericsson Cycles 467

10–8 Brayton Cycle: The Ideal Cycle for Gas-Turbine

Engines 470

Development of Gas Turbines 473

Deviation of Actual Gas-Turbine Cycles from Idealized

Ones 475

10–9 The Brayton Cycle with Regeneration 477

10–10 The Brayton Cycle with Intercooling,

Reheating,

and Regeneration 479

10–11 Ideal Jet-Propulsion Cycles 483

Modifications to Turbojet Engines 487

10–12 Second-Law Analysis of Gas Power Cycles 489

Topic of Special Interest: Saving Fuel and Money by

Driving Sensibly 493

Summary 499

References and Suggested Readings 500

Problems 500

C H A P T E R E L E V E N

VAPOR AND COMBINED POWER

CYCLES 515

11–1 The Carnot Vapor Cycle 516

11–2 Rankine Cycle: The Ideal Cycle for Vapor Power

Cycles 516

Energy Analysis of the Ideal Rankine Cycle 517

11–3 Deviation of Actual Vapor Power Cycles from

Idealized Ones 520

11–4 How Can We Increase the Efficiency

of the

Rankine

Cycle? 522

Lowering the Condenser Pressure (Lowers Tlow,avg) 523

Superheating the Steam to High Temperatures

(Increases Thigh,avg) 523

Increasing the Boiler Pressure (Increases Thigh,avg) 523

11–5 The Ideal Reheat Rankine Cycle 526

11–6 The Ideal Regenerative Rankine Cycle 530

Open Feedwater Heaters 531

Closed Feedwater Heaters 532

11–7 Second-Law Analysis of Vapor Power Cycles 538

11–8 Cogeneration 541

11–9 Combined Gas–Vapor Power Cycles 545

Topic of Special Interest: Binary Vapor Cycles 548

Summary 549

References and Suggested Readings 550

Problems 550

C H A P T E R T W E LV E

REFRIGERATION CYCLES 565

12–1 Refrigerators and Heat Pumps 566

12–2 The Reversed Carnot Cycle 567

12–3 The Ideal Vapor-Compression Refrigeration

Cycle 568

12–4 Actual Vapor-Compression Refrigeration

Cycle 571

12–5 Second-Law Analysis of Vapor-Compression

Refrigeration

Cycle 573

12–6 Selecting the Right Refrigerant 578

12–7 Heat Pump Systems 580

12–8 Innovative Vapor-Compression Refrigeration

Systems 582

Cascade Refrigeration Systems 582

Multistage Compression Refrigeration Systems 584

Multipurpose Refrigeration Systems with a Single

Compressor 586

Liquefaction of Gases 587

12–9 Gas Refrigeration Cycles 591

12–10 Absorption Refrigeration Systems 594

Topic of Special Interest: Thermoelectric Power Generation

and Refrigeration Systems 598

Summary 600

References and Suggested Readings 600

Problems 601

C H A P T E R T H I R T E E N

THERMODYNAMIC PROPERTY

RELATIONS 615

13–1 A Little Math—Partial Derivatives and Associated

Relations 616

Partial Differentials 617

Partial Differential Relations 618

13–2 The Maxwell Relations 620

13–3 The Clapeyron Equation 622

13–4 General Relations for du, dh, ds, cv, and cp 625

Internal Energy Changes 625

Enthalpy Changes 626

**Entropy Changes** 627

Specific Heats cv and cp 627

13–5 The Joule-Thomson Coefficient 631

13–6 The Δh, Δu, and Δs of Real Gases 633

Enthalpy Changes of Real Gases 633

Internal Energy Changes of Real Gases 635

Entropy Changes of Real Gases 635

Summary 638

References and Suggested Readings 639

Problems 639

C H A P T E R F O U RT E E N

GAS MIXTURES 645

14–1 Composition of a Gas Mixture: Mass and Mole

Fractions 646

14–2 P-v-T Behavior of Gas Mixtures: Ideal and Real

Gases 647

Ideal-Gas Mixtures 648

Real-Gas Mixtures 649

14–3 Properties of Gas Mixtures: Ideal and Real Gases 652

Ideal-Gas Mixtures 653

Real-Gas Mixtures 656

Topic of Special Interest: Chemical Potential and

the Separation Work of Mixtures 660

Summary 669

References and Suggested Readings 669

Problems 670

C H A P T E R F I F T E E N

GAS–VAPOR MIXTURES AND AIR-CONDITIONING 677

15–1 Dry and Atmospheric Air 678

15–2 Specific and Relative Humidity of air 679

15–3 Dew-Point Temperature 682

15–4 Adiabatic Saturation and Wet-Bulb Temperatures 684

15–5 The Psychrometric Chart 686

15–6 Human Comfort and Air-Conditioning 688

15–7 Air-Conditioning Processes 690

Simple Heating and Cooling (ω = constant) 691

Heating with Humidification 692

Cooling with Dehumidification 693

Evaporative Cooling 695

Adiabatic Mixing of Airstreams 696

Wet Cooling Towers 698

Summary 700

References and Suggested Readings 701

Problems 702

C H A P T E R S I X T E E N

CHEMICAL REACTIONS 711

16–1 Fuels and Combustion 712

16–2 Theoretical and Actual Combustion Processes 715

16–3 Enthalpy of Formation and Enthalpy of Combustion 721

16–4 First-Law Analysis of Reacting Systems 725

Steady-Flow Systems 725

Closed Systems 727

16–5 Adiabatic Flame Temperature 730

16–6 Entropy Change of Reacting Systems 733

16–7 Second-Law Analysis of Reacting Systems 735

Topic of Special Interest: Fuel Cells 740

Summary 741

References and Suggested Readings 742

Problems 743

C H A P T E R S E V E N T E E N

CHEMICAL AND PHASE EQUILIBRIUM 753

17–1 Criterion for Chemical Equilibrium 754

17–2 The Equilibrium Constant for Ideal-Gas Mixtures 756

17–3 Some Remarks About the KP of Ideal-Gas Mixtures 760

17–4 Chemical Equilibrium for Simultaneous Reactions 764

17–5 Variation of KP with Temperature 766

17–6 Phase Equilibrium 768

Phase Equilibrium for a Single-Component System 768

The Phase Rule 769

Phase Equilibrium for a Multicomponent System 769

Summary 775

References and Suggested Readings 776

Problems 776

C H A P T E R E I G H T E E N

COMPRESSIBLE FLOW 785

18–1 Stagnation Properties 786

18–2 Speed of Sound and Mach Number 789

18–3 One-Dimensional Isentropic Flow 792

Variation of Fluid Velocity with Flow Area 793

Property Relations for Isentropic Flow of Ideal Gases 795

18–4 Isentropic Flow Through Nozzles 798

Converging Nozzles 798

Converging–Diverging Nozzles 802

18–5 Shock Waves and Expansion Waves 806

Normal Shocks 806

Oblique Shocks 811

Prandtl–Meyer Expansion Waves 815

18–6 Duct Flow with Heat Transfer and Negligible

Friction (Rayleigh Flow) 819

Property Relations for Rayleigh Flow 824

Choked Rayleigh Flow 825

18–7 Steam Nozzles 828

Summary 831

References and Suggested Readings 832

Problems 832

A P P E N D I X O N E

PROPERTY TABLES AND CHARTS

(SI UNITS) 839

Table A–1 Molar mass, gas constant, and criticalpoint properties 840

Table A–2 Ideal-gas specific heats of various common gases 841

Table A–3 Properties of common liquids, solids, and foods 844

Table A–4 Saturated water—Temperature table 846

Table A–5 Saturated water—Pressure table 848

Table A–6 Superheated water 850

Table A–7 Compressed liquid water 854

Table A–8 Saturated ice–water vapor 855

Figure A–9 T-s diagram for water 856

Figure A–10 Mollier diagram for water 857

Table A–11 Saturated refrigerant-134a—Temperature table 858

Table A–12 Saturated refrigerant-134a—Pressure table 860

Table A–13 Superheated refrigerant-134a 861

Figure A–14 P-h diagram for refrigerant-134a 863

Figure A–15 Nelson–Obert generalized compressibility chart 864

Table A–16 Properties of the atmosphere at high altitude 866

Table A–17 Ideal-gas properties of air 867

Table A–18 Ideal-gas properties of nitrogen, N2 869

Table A–19 Ideal-gas properties of oxygen, O2 871

Table A–20 Ideal-gas properties of carbon dioxide, CO2 873

Table A–21 Ideal-gas properties of carbon monoxide, CO 875

Table A–22 Ideal-gas properties of hydrogen, H2 877

Table A–23 Ideal-gas properties of water vapor, H2O 878

Table A–24 Ideal-gas properties of monatomic oxygen, O 880

Table A–25 Ideal-gas properties of hydroxyl, OH 880

Table A–26 Enthalpy of formation, Gibbs function of

formation, and absolute entropy at 25°C, 1 atm 881

Table A–27 Properties of some common fuels and hydrocarbons 882

Table A–28 Natural logarithms of the equilibrium constant Kp 883

Figure A–29 Generalized enthalpy departure chart 884

Figure A–30 Generalized entropy departure chart 885

Figure A–31 Psychrometric chart at 1 atm total pressure 886

Table A–32 One-dimensional isentropic compressible flow functions for an ideal gas with k = 1.4 887

Table A–33 One-dimensional normal-shock functions for an ideal gas with k = 1.4 888

Table A–34 Rayleigh flow functions for an ideal gas with k = 1.4 889

A P P E N D I X TWO

PROPERTY TABLES AND CHARTS

(ENGLISH UNITS) 891

Table A–1E Molar mass, gas constant, and criticalpoint properties 892

Table A–2E Ideal-gas specific heats of various common gases 893

Table A–3E Properties of common liquids, solids, and foods 896

Table A–4E Saturated water—Temperature table 898

Table A–5E Saturated water—Pressure table 900

Table A–6E Superheated water 902

Table A–7E Compressed liquid water 906

Table A–8E Saturated ice–water vapor 907

Figure A–9E T-s diagram for water 908

Figure A–10E Mollier diagram for water 909

Table A–11E Saturated refrigerant-134a—Temperature table 910

Table A–12E Saturated refrigerant-134a—Pressure table 911

Table A–13E Superheated refrigerant-134a 912

Figure A–14E P-h diagram for refrigerant-134a 914

Table A–16E Properties of the atmosphere at high altitude 915

Table A–17E Ideal-gas properties of air 916

Table A–18E Ideal-gas properties of nitrogen, N2 918

Table A–19E Ideal-gas properties of oxygen, O2 920

Table A–20E Ideal-gas properties of carbon dioxide, CO2 922

Table A–21E Ideal-gas properties of carbon monoxide, CO 924

Table A–22E Ideal-gas properties of hydrogen, H2 926

Table A–23E Ideal-gas properties of water vapor, H2O 928

Table A–26E Enthalpy of formation, Gibbs function of formation, and absolute entropy at 77°F, 1 atm 929

Table A–27E Properties of some common fuels and hydrocarbons 930

Figure A–31E Psychrometric chart at 1 atm total pressure 931

INDEX 933

NOMENCLATURE 945

CONVERSION FACTORS 947