CHAPTER CHAPTER TWO PROPERTIES OFPURESUBSTANCES63 ONE Pressure The Manometer 33

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CHAPTER ONE BASICCONCEPTSOFTHERMODYNAMICS 1-1 1-2 1-3 1-4 1-5 1-6 1-7 1-8 1-9 Thermodynamics and Energy 2 ApplicationAreasof Thermodynamics 3 A Note on Dimensions and Units 3 SomeSI and EnglishUnits

1 CHAPTER ONE BASICCONCEPTSOFTHERMODYNAMICS Thermodynamics and Energy 2 ApplicationAreasof Thermodynamics 3 A Note on Dimensions and Units 3 SomeSI and EnglishUnits 5 DimensionalHomogeneity 7 Closed and Open Systems Properties of a System 10 State and Equilibrium 12 Processes and Cycles 13 The Steady-Flow Process 14 Forms of Energy 14 Some PhysicalInsightto Internal Energy 16 Moreon Nuclear Energy 18 Energy and Environment 19 Ozoneand Smog 21 Acid Rain 21 The GreenhouseEffect:GlobalWarming and ClimateChange 22 Temperature and the Zeroth Law of Thermodynamics 25 TemperatureScales Pressure 28 Variationof Pressurewith Depth The Manometer 33 Other PressureMeasurementDevices Barometer and the Atmospheric Pressure 1-13 Problem-Solving Technique 38 ARemarkof SignificantDigits 40 EngineeringSoftwarePackages41 EngineeringEquationSolver(EES) 42 Thermodynamic Aspects of Biological Systems 43 Foodand Exercise 45 Dieting Summary 51 Referencesand SuggestedReading 51 Problems 52 CHAPTER TWO PROPERTIES OFPURESUBSTANCES Pure Substance 64 Phases of a Pure Substance Phase-Change Processes of Pure Substances 65 CompressedLiquid and SaturatedLiquid 65 SaturatedVaporand SuperheatedVapor 66 SaturationTemperatureandSaturationPressure 67 SomeConsequencesof Tsatand PsatDependence Property Diagrams for Phase-Change Processes 70 1 The T-vDiagram 70 2 The P-vDiagram 71 Extendingthe Diagramsto Include the Solid Phase 73 3 The P-T Diagram 74 The P-v-TSurface Property Tables 77 Enthalpy-A CombinationProperty 77 la SaturatedLiquid and SaturatedVaporStates 78 Ib SaturatedLiquid-Vapor Mixture 79 2 SuperheatedVapor 83 3 Compressed Liquid 84 ReferenceStateand ReferenceValues The Ideal-Gas Equation of State Is WaterVaporan IdealGas? 89 Compressibility Factor-A Measure of Deviation from Ideal-Gas Behavior Other Equations of State 94 Van der WaalsEquationof State 94 Beattie-BridgemanEquationof State 95 Benedict-Webb-RubinEquationof State 95 Virial Equationof State Specific Heats vii

2 2-10 Internal Energy, Enthalpy, and Specific Heats of Ideal Gases 100 Specific-Heat Relations of Ideal Gases Internal Energy, Enthalpy, and Specific Heats of Solids and Liquids 105 Internal Energy Changes 106 Enthalpy Changes 106 Vapor Pressure and Phase Equilibrium Summary 111 References and Suggested Reading 112 Problems 112 CHAPTER THREE ENERGYTRANSFERBYHEAT,WORK, ANDMASS Heat Transfer 124 Historical Background on Heat Energy Transfer by Work 126 Electrical Work Mechanical Forms of Work Moving Boundary Work Shaft Work Spring Work Other Mechanical Forms of Work 138 Nonmechanical Forms of Work 140 Conservation of Mass Principle 141 Mass and Volume Flow Rates 141 Conservation of Mass Principle 143 Mass Balance for Steady-Flow Processes Flow Work and the Energy of a Flowing Fluid 147 Total Energy of a Flowing Fluid 148 Energy Transport by Mass 148 Mechanisms of Heat Transfer 150 Summary 155 Referencesand SuggestedReading 156 Problems CHAPTER FOUR THEFIRSTLAWOFTHERMODYNAMICS The First Law of Thermodynamics EnergyBalance Energy Change of a System, 6.Esystem 168 Mechanisms of Energy Transfer, E;nand Eout 168 Energy Balance for Closed Systems 170 Energy Balance for Steady-Flow Systems 181 Energy Balance for Steady-Flow Systems 182 Some Steady-Flow Engineering Devices Nozzlesand Diffusers Turbinesand Compressors a ThrottlingValves 190 MixtureChambers 192 4b Heat Exchangers Pipeand DuctFlow 196 Energy Balance for Unsteady-Flow Processes 197 Mass Balance 198 EnergyBalance 198 Refrigeration and Freezing 9f Foods ThermalPropertiesof Foods 205 Refrigeration of Fruits and Vegetables 207 Refrigeration of Meats 208 Poultry Products 209 Summary 214 Referenced and Suggested Reading 215 Problems CHAPTER FIVE THESECONDLAWOFTHERMODYNAMICS Introduction to the Second Law 246 Thermal Energy Reservoirs 247 Heat Engines 247 CanWeSave Ouot? 250 The Second Law of Thermodynamics: Kelvin-Planck Statement 253 Energy Conversion Efficiencies 253 Refrigerators and Heat Pumps 257 CoefficientPerformance 258 Heat Pumps 259 The Second Lawof Thermodynamics: ClausiusStatement 262 Equivalence of the Two Statements 262 Perpetual-Motion Machines 263 Reversible and Irreversible Processes 265 Irreversibilities 267 Internally and Externally Reversible Processes The Carnot Cycle 269 The Reversed Carnot Cycle 271

3 ~"r"i".c.'i:_~i'.r:~;)[tf'::~ft::l~ ix ~0:;,:;;~,:7lt:t1;~jf!a~~Iiif:'f";.,"'. CONTENTS.':. 5-9 The Carnot Principles The Thermodynamic Temperature Scale 5-11 The Carnot Heat Engine 275 The Qualityof Energy 276 Quantityversus Quality in DailyLife The Carnot Refrigerator and Heat Pump Household Refrigerators 281 Summary 285 Referencesand SuggestedReading 286 Problems 286 CHAPTER ENTROPY301 SIX EntropyChangeof a System,Ssystem 348 Mechanismsof EntropyTransfer,Sinand Soul 348 Entropy Generation, Sgen 350 Closed Systems 351 Control Volumes 351 Entropy Generation Associated with a Heat Transfer Process 358 Reducing the Cost of Compressed Air 360 Summary 370 ReferencesandSuggestedReading 372 Problems 372 CHAPTER SEVEN EXERGY: A MEASUREOF WORKPOTENTIAL Entropy ASpecialCase:Internally Reversible IsothermalHeatTransferProcesses 304 The Increase of Entropy Principle 305 Some Remarksabout Entropy 307 Entropy Change of Pure Substances 309 Isentropic Processes 313 Property Diagrams Involving Entropy 314 What Is Entropy? 316 Entropyand EntropyGenerationin DailyLife 318 The T ds Relations 319 Entropy Change of Liquids and Solids 321 The Entropy Change of Ideal Gases 324 ConstantSpecific Heats(ApproximateAnalysis) 325 VariableSpecific Heats(ExactAnalysis) 326 IsentropicProcessesof IdealGases 327 ConstantSpecific Heats(ApproximateAnalysis) 328 VariableSpecific Heats(ExactAnalysis) 328 RelativePressureand RelativeSpecificVolume Reversible Steady-Flow Work 332 Proofthat Steady-FlowDevicesDeliverthe Mostand Consumethe LeastWorkwhen the ProcessIs Reversible Minimizing the Compressor Work 336 MultistageCompressionwith Intercooling Isentropic Efficiencies of Steady-Flow Devices 340 IsentropicEfficiencyof Turbines 341 IsentropicEfficienciesof Compressorsand Pumps 343 IsentropicEfficiencyof Nozzles Entropy Balance Exergy: Work Potential of Energy Exergy(Work Potential)Associatedwith Kinetic Energy,ke 395 ExergyAssociatedwith PotentialEnergy,pe 395 Reversible Work and Irreversibility 395 Second-Law Efficiency, 'YJn 399 Exergy Change of a System 402 Energyof a Fixed Mass:Nonflow(or ClosedSystem) Exergy 405 Exergyof a FlowStream: Flow(or Stream)Exergy 407 Exergy Transfer by Heat, Work, and Mass ExergyTransferby HeatTransfer,Q 410 ExergyTransferby Work, W 411 ExergyTransferby Mass,m 412 The Decrease of Exergy Principle and Exergy Destruction 410 Exergy Destruction 413 Exergy Balance: Closed Systems 412 Exergy Balance: Control Volumes 424 ExergyBalancefor Steady-FlowSystems 425 Second-Law Aspects of Daily Life 432 Summary 435 Referencesand SuggestedReading 437 Problems CHAPTER EIGHT GASPOWERCYCLES Basic Considerations in the Analysis of Power Cycles 452

4 '~,',"~~'.~~[',.y:",:..'.;;;:tj"..,';:1}!ftf"8t?:',: x~ CONTENTS The Carnot Cycle and Its Value in Engineering 454 Air-Standard Assumptions 456 An Overview of Reciprocating Engines 456 Otto Cycle: The Ideal Cycle for Spark-Ignition Engines 457 Diesel Cycle: The Ideal Cycle for Compression- Ignition Engines 463 Stirling and Ericsson Cycles 466 Brayton Cycle: The Ideal Cycle for Gas-Turbine Engines 470 Development of Gas Turbines 473 Deviation of Actual Gas-Turbine Cycles from Idealized Ones The Brayton Cycle with Regeneration The Brayton Cycle with Intercooling, Reheating, and Regeneration Ideal Jet-Propulsion Cycles 483 Modifications to Turbojet Engines Second-Law Analysis of Gas Power Cycles 490 Saving Fuel and Money by Driving Sensibly 493 BeforeDriving 494 While Driving 496 After Driving 498 Summary 499 Referencesand SuggestedReading 501 Problems 501 CHAPTER NINE VAPORANDCOMBINEDPOWERCYCLES The Carnot Vapor Cycle 514 Rankine Cycle: The Ideal Cycle for Vapor Power Cycles 515 Energy Analysis of the Ideal Rankine Cycle 516 Deviation of Actual Vapor Power Cycles from Idealized Ones 519 How Can We Increase the Efficiency of the Rankine Cycle? Loweringthe CondenserPressure (Lowers Tiaw,av) Superheating the Steam to High Temperatures (Increases Thigh,av) Increasing the Boiler Pressure (Increases Thigh,av) The Ideal Reheat Rankine Cycle The Ideal Regenerative Rankine Cycle 529 Open FeedwaterHeaters 529 ClosedFeedwaterHeaters Second-Law Analysis of Vapor Power Cycles Cogeneration Combined Gas-Vapor Power Cycles 543 Binary Vapor Cycles 547 Summary549 ReferencesandSuggestedReading 550 Problems 550 CHAPTER TEN REFRIGERATION CYCLES Refrigerators and Heat Pumps TheReversedCarnotCycle The Ideal Vapor-Compression Refrigeration Cycle Actual Vapor-Compression RefrigerationCycle Selecting the Right Refrigerant Heat Pump Systems Innovative Vapor-Compression Refrigeration Systems 576 Cascade RefrigerationSystems 577 MultistageCompressionRefrigerationSystems 579 MultipurposeRefrigerationSystemswith a SingleCompressor 582 Liquefactionof Gases Gas Refrigeration Cycles Absorption Refrigeration Systems 588 Thermoelectric Power Generation and Refrigeration Systems 590 Summary 592 Referencesand SuggestedReading 593 Problems 594 CHAPTER ELEVEN THERMODYNAMIC PROPERTYRELATIONS A Little Math-Partial Derivatives and Associated Relations 604

5 "~ '.. PartialDifferentia,s 605 PartialDifferentialRelations The Maxwell Relations The Clapeyron Equation General Relations for du, dh, ds, Cv, and Cp 613 InternalEnergyChanges 613 EnthalpyChanges 614 EntropyChanges 615 Specific Heats Cyand Cp The Joule-Thomson Coefficient The jj.h, jj.u, and jj.s of Real Gases 622 EnthalpyChangesof RealGases 622 Internal EnergyChangesof RealGases 623 EntropyChangesof RealGases 623 Summary 626 Referencesand SuggestedReading 627 Problems 627 CHAPTER TWELVE GASMIXTURES Composition of a Gas Mixture: Mass and Mole Fractions P-v-TBehavior of Gas Mixtures: Ideal and Real Gases 636 Ideal-GasMixtures 637 Real-GasMixtures Properties of Gas Mixtures: Ideal and Real Gases 641 Ideal-GasMixtures 642 Real-GasMixtures 645 Chemical Potential and the Separation Work of Mixtures 648 IdealGasMixturesand IdealSolutions 651 Minimum Work of Separationof Mixtures 653 ReversibleMixing Processes 654 Second-LawEfficiency 654 Special-Case:Separationof a Two-ComponentMixture 655 An Application: DesalinationProcesses 656 Summary 659 Referencesand SuggestedReading 660 Problems 660 CHAPTER THIRTEEN GAS-VAPORMIXTURESAND AIR-CONDITIONING Dry and AtmosphericAir Specific and Relative Humidity of Air Dew-Point Temperature Adiabatic Saturation and Wet-Bulb Temperatures The Psychrometric Chart Human Comfort and Air-Conditioning Air-Conditioning Processes SimpleHeatingandCooling(w = constant) Heatingwith Humidification Coolingwith Dehumidification EvaporativeCooling Adiabatic Mixingof Airstreams Wet CoolingTowers 689 Summary 691 Referencesand SuggestedReading 692 Problems 693 CHAPTER FOURTEEN CHEMICAL REACTIONS Fuels and Combustion Theoretical and Actual Combustion Processes Enthalpy of Formation and Enthalpy of Combustion First-Law Analysis of Reacting Systems 715 Steady-FlowSystems 715 Closed Systems Adiabatic Flame Temperature Entropy Change of Reacting Systems Second-Law Analysis of Reacting Systems 724 Fuel Cells 730 Summary 732 Referencesand SuggestedReading 733 Problems 734 CHAPTER FIFTEEN CHEMICAL ANDPHASEQUILIBRIUM Criterion for Chemical Equilibrium The Equilibrium Constant for Ideal-Gas Mixtures Some Remarks about the Kp of Ideal-Gas Mixtures Chemical Equilibrium for Simultaneous Reactions 754

6 - -- xii CONTENTS 15-5 Variation of Kp with Temperature Phase Equilibrium 757 Phase Equilibriumfor a Single-ComponentSystem 758 The PhaseRule 759 PhaseEquilibriumfor a MulticomponentSystem 760 Summary 765 Referencesand SuggestedReading 766 Problems 766 CHAPTER SIXTEEN THERMODYNAMICS OF HIGH-SPEED GASFLOW Stagnation Properties Velocity of Sound and Mach Number One-Dimensional Isentropic Flow 782 Variationof FluidVelocitywith FlowArea 784 PropertyRelationsfor IsentropicFlowof IdealGases Isentropic Flow through Nozzles 788 ConvergingNozzles 789 Converging-Diverging Nozzles Normal Shocks in Nozzle Flow Flow through Actual Nozzles and Diffusers Steam Nozzles 810 Summary 813 Referencesand SuggestedReading 815 Problems 815 APPENDIX 1 PROPERTYTABLESANDCHARTS (SI UNITS) 823 Table A-I Table A-2 Table A-3 Table A-4 Table A-5 Table A-6 Table A-7 Table A-8 Molar Mass, Gas Constant, and Critical-Point Properties 824 Ideal-Gas Specific Heats of Various Common Gases 825 Properties of Common Liquids, Solids, and Foods 828 Saturated Water- Temperature Table 830 Saturated Water-Pressure Table 832 Superheated Water 834 Compressed Liquid Water 838 Saturated Ice Water-Vapor 839 Figure A-9 Figure A-lO Table A-ll Table A-12 Table A-13 FigureA-14 TableA-15 TableA-16 Table A-17 Table A-18 T-s Diagram for Water 840 Monier Diagram for Water 841 Saturated Refrigerant -134a- Temperature Table 842 Saturated Refrigerant -134a- Pressure Table 843 Superheated Refrigerant-134a 844 P-h Diagram for Refrigerant-134a 846 One-Dimensional Isentropic Compressible-Flow Functions for an Ideal Gas with Constant Specific Heats and Molar Mass, and k = One-Dimensional Normal-Shock Functions for an Ideal Gas with Constant Specific Heats and Molar Mass, and k = of Air 849 of Nitrogen, Nz 851 Table A-19 of Oxygen, Oz 853 Table A-20 Table A-21 Table A-22 Table A-23 Table A-24 Table A-25 Table A-26 Table A-27 Table A-28 Table A-29 of Carbon Dioxide, COz 855 of Carbon Monoxide, CO 857 of Hydrogen, Hz 859 of Water Vapor, HzO 860 of Monatomic Oxygen, a 862 of Hydroxyl, OH 862 Enthalpy of Formation, Gibbs Function of Formation, and Absolute Entropy at 25 C, 1 atm 863 Properties of Some Common Fuels and Hydrocarbons 864 Logarithms to Base e of the Equilibrium Constant Kp 865 Properties of the Atmosphere at High Altitude 866 Figure A-30a Nelson-Obert Generalized Compressibility Chart- Low Pressures 867

7 Figure A-30b Nelson-Obert Generalized Compressibility Chart- Intermediate Pressures 868 Figure A-30c Nelson-Obert Generalized Compressibility Chart- High Pressures 869 Figure A-31 Figure A-32 Figure A-33 Generalized Enthalpy Departure Chart 870 Generalized Entropy Departure Chart 871 Psychrometric Chart at 1 atm Total Pressure 872 APPENDIX 2 PROPERTY TABLESANDCHARTS (ENGLISHUNITS) 873 TableA-IE Table A-2E TableA-3E Molar Mass, Gas Constant, and Critical-Point Properties 874 Ideal-Gas Specific Heats of Various Common Gases 875 Properties of Common Liquids, Solids and Foods 878 TableA-4E Saturated Water- Temperature Table 880 Table A-5E Saturated Water-Pressure Table 881 Table A-6E Superheated Water 883 Table A-7E Compressed Liquid Water 887 TableA-8E Saturated Ice-Water Vapor 888 Figure A-9E T-s Diagram for Water 889 Figure A-WE Monier Diagram for Water 890 Table A-lIE Saturated Refrigerant -134a- Temperature Table 891 Table A-12E Saturated Refrigerant-134a- Pressure Table 892 Table A-13E Superheated Refrigerant -134a 893 Figure A-14E P-h Diagram for Refrigerant-134a 895 Table A-17E of Air 896 Table A-18E Table A-19E Table A-20E Table A-2lE Table A-22E Table A-23E Table A-26E Table A-27E Table A-29E of Nitrogen, N2 898 of Oxygen, O2 900 of Carbon Dioxide, CO2 902 of Carbon Monoxide, CO 904 of Hydrogen, H2 906 of Water Vapor, H2O 907 Enthalpy of Formation, Gibbs Function of Formation, and Absolute Entropy 909 Properties of Some Common Fuels and Hydrocarbons 910 Properties of the Atmosphere at High Altitude 911 Figure A-33E Psychrometric Chart at 1 atm Total Pressure 912 APPENDIX 3 INTRODUCTION TOEES 913 Index 926

Chapter 1 Introduction and Basic Concepts

Chapter 1 Introduction and Basic Concepts 1-1 Thermodynamics and Energy Application Areas of Thermodynamics 1-2 Importance of Dimensions and Units Some SI and English Units Dimensional Homogeneity Unity