Contents at a Glance Introduction... 1 Part I: Covering the Basics in Thermodynamics... 7 Chapter 1: Thermodynamics in Everyday Life...9 Chapter 2: Laying the Foundation of Thermodynamics...15 Chapter 3: Working with Phases and Properties of Substances...39 Chapter 4: Work and Heat Go Together Like Macaroni and Cheese...57 Part II: Employing the Laws of Thermodynamics... 75 Chapter 5: Using the First Law in Closed Systems...77 Chapter 6: Using the First Law in Open Systems...91 Chapter 7: Governing Heat Engines and Refrigerators with the Second Law...111 Chapter 8: Entropy Is the Demise of the Universe...123 Chapter 9: Analyzing Systems Using the Second Law of Thermodynamics...145 Part III: Planes, Trains, and Automobiles: Making Heat Work for You... 165 Chapter 10: Working with Carnot and Brayton Cycles...167 Chapter 11: Working with Otto and Diesel Cycles...197 Chapter 12: Working with Rankine Cycles...221 Chapter 13: Cooling Off with Refrigeration Cycles...243 Part IV: Handling Thermodynamic Relationships, Reactions, and Mixtures... 265 Chapter 14: Understanding the Behavior of Real Gases...267 Chapter 15: Mixing Gases That Don t React with Each Other...277 Chapter 16: Burning Up with Combustion...303 COPYRIGHTED MATERIAL Part V: The Part of Tens... 325 Chapter 17: Ten Famous Names in Thermodynamics...327 Chapter 18: Ten More Cycles of Note...331 Appendix: Thermodynamic Property Tables... 341 Index... 351
Table of Contents Introduction... 1 About This Book...1 Conventions Used in This Book...2 What You re Not to Read...2 Foolish Assumptions...3 How This Book Is Organized...3 Part I: Covering the Basics in Thermodynamics...3 Part II: Employing the Laws of Thermodynamics...4 Part III: Planes, Trains, and Automobiles: Making Heat Work for You...4 Part IV: Handling Thermodynamic Relationships, Reactions, and Mixtures...5 Part V: The Part of Tens...5 Icons Used in This Book...5 Where to Go from Here...6 Part I: Covering the Basics in Thermodynamics... 7 Chapter 1: Thermodynamics in Everyday Life......................9 Grasping Thermodynamics...9 Examining Energy s Changing Forms...10 Kinetic energy...11 Potential energy...11 Internal energy...11 Watching Energy and Work in Action...12 Engines: Letting energy do work...12 Refrigeration: Letting work move heat...13 Getting into Real Gases, Gas Mixtures, and Combustion Reactions...13 Discovering Old Names and New Ways of Saving Energy...14 Chapter 2: Laying the Foundation of Thermodynamics.............15 Defining Important Thermodynamic Properties...16 Eyeing general measurement basics...16 Mass...17 Pressure...18 Temperature...19 Density...21 Energy...22 Enthalpy...27 Specific heat...27 Entropy...29
x Thermodynamics For Dummies Understanding Thermodynamic Processes...29 Creating a path for a process...30 Finding the state at each end of a path: The state postulate...31 Connecting processes to make a cycle...32 Discovering Nature s Law and Order on Temperature, Energy, and Entropy...34 The zeroth law on temperature...34 The first law on energy conservation...35 The second law on entropy...36 The third law on absolute zero...37 Chapter 3: Working with Phases and Properties of Substances....39 It s Just a Phase: Describing Solids, Liquids, and Gases...40 The phase diagram...41 The T-v diagram...42 The P-v diagram...44 Knowing How Phase Changes Occur...45 From compressed liquid to saturated liquid...46 From saturated liquid to saturated vapor...47 From saturated vapor to superheated vapor...50 Finding Thermodynamic Properties from Tables...50 Figuring out linear interpolation...51 Interpolating with two variables...52 Good Gases Have Ideal Behavior...54 Chapter 4: Work and Heat Go Together Like Macaroni and Cheese.....................................57 Work Can Do Great Things...58 Working with springs...59 Turning a shaft...61 Accelerating a car...62 Moving with pistons...63 Figuring out boundary work...66 Heating Things Up, Cooling Things Down...67 Getting hot with boilers...68 Cooling off with condensers...70 Chilling with evaporators...71 Part II: Employing the Laws of Thermodynamics... 75 Chapter 5: Using the First Law in Closed Systems.................77 Conserving Mass in a Closed System...77 Balancing Energy in a Closed System...78
Table of Contents xi Applying the First Law to Ideal-Gas Processes...81 Working with constant volume...81 Working with constant pressure...82 Working with constant temperature...85 Working with an adiabatic process...86 Applying the First Law to Processes with Liquids and Solids...88 Chapter 6: Using the First Law in Open Systems..................91 Conserving Mass in an Open System...91 Defining mass and volumetric flow rates...92 Applying conservation of mass to a system...93 Balancing Mass and Energy in a System...94 When Time Stands Still: The Steady State Process...95 Using the First Law on Four Common Open-System Processes...97 Flowing through nozzles and diffusers...98 Working with pumps, compressors, and turbines...100 Moving energy with heat exchangers...102 Reducing pressure with throttling valves...104 When Time Is of the Essence: The Transient Process...106 Making assumptions for the energy balance...107 Analyzing a transient process...108 Chapter 7: Governing Heat Engines and Refrigerators with the Second Law............................111 Looking at the Impact of the Second Law...112 Defining Thermal Energy Reservoirs...112 Parameters of a thermal reservoir...113 Considering highs and lows...114 Working with the Kelvin-Planck Statement on Heat Engines...114 Characterizing heat engines...115 Determining thermal efficiency...117 Chilling with the Clausius Statement on Refrigeration...118 Characterizing refrigerators...119 Finding the coefficient of performance...120 Chapter 8: Entropy Is the Demise of the Universe................123 What Is Entropy?...124 Taking a microscopic view of entropy...124 Looking at entropy on a macroscopic level...125 Coping with the Increase in Entropy Principle...126 Working with T-s Diagrams...128 Using T-ds Relationships...130 Calculating Entropy Change...131 For pure substances...131 For liquids and solids...134 For ideal gases...136
xii Thermodynamics For Dummies Analyzing Isentropic Processes...139 Using constant specific heat...140 Using relative pressure and relative volume...142 Balancing Entropy in a System...143 Chapter 9: Analyzing Systems Using the Second Law of Thermodynamics..............................145 Measuring Work Potential with Energy Availability...146 Determining the Change in Availability...147 Calculating availability in closed systems...147 Calculating availability in open systems with steady flow...151 Calculating availability in open systems with transient flow...154 Balancing the Availability of a System...156 Transferring availability using work processes...157 Transferring availability with heat transfer processes...158 Transferring availability with mass flow...158 Understanding the Decrease in Availability Principle...159 Figuring Out Reversible Work and Irreversibility...160 Calculating the Second-Law Efficiency of a System...162 Part III: Planes, Trains, and Automobiles: Making Heat Work for You... 165 Chapter 10: Working with Carnot and Brayton Cycles............167 Analyzing the Ideal Heat Engine: The Carnot Cycle...168 Examining the four processes in a Carnot cycle...169 Calculating Carnot efficiency...171 Working with the Ideal Gas Turbine Engine: The Brayton Cycle...172 Examining the four processes in a Brayton cycle...173 Analyzing the Brayton cycle...175 Determining Brayton cycle efficiency...181 Calculating Brayton cycle irreversibility...182 Improving the Brayton Cycle with Regeneration...184 Adding Intercooling and Reheating to the Brayton Cycle...186 Looking at how intercooling and reheating affect the Brayton cycle...186 Analyzing the effects of intercooling and reheating...188 Deviating from Ideal Behavior: Actual Brayton Cycle Performance...190 Flying the Brayton Cycle in Jet Propulsion...191 Seeing what happens in an ideal turbojet cycle...192 Analyzing the jet engine cycle...194
Table of Contents xiii Chapter 11: Working with Otto and Diesel Cycles................197 Understanding the Basics of Reciprocating Engines...197 Working with the Ideal Spark Ignition Engine: The Otto Cycle...201 Analyzing the Otto cycle...202 Calculating Otto cycle efficiency...208 Calculating Otto cycle irreversibility...208 Working with the Ideal Compression Ignition Engine: The Diesel Cycle...212 Examining the four processes in a Diesel cycle...212 Analyzing the Diesel cycle...213 Calculating diesel cycle efficiency...218 Calculating diesel cycle irreversibility...219 Chapter 12: Working with Rankine Cycles......................221 Understanding the Basics of the Rankine Cycle...222 Examining the Four Processes of the Rankine Cycle...223 Analyzing the Cycle Using Steam Tables...226 Calculating Rankine cycle efficiency...228 Calculating Rankine cycle irreversibility...228 Improving the Rankine Cycle with Reheat...230 Improving the Rankine Cycle with Regeneration...233 Deviating from Ideal Behavior: Actual Rankine Cycle Performance...239 Chapter 13: Cooling Off with Refrigeration Cycles...............243 Understanding the Basics of Refrigeration Cycles...244 Chilling with the Reverse Brayton Cycle...244 Examining the four processes of the reverse Brayton cycle...245 Analyzing the cycle with constant specific heat...247 Calculating the reverse Brayton cycle coefficient of performance...249 Calculating irreversibility for Brayton s refrigerator...250 Cooling with the Vapor-Compression Refrigerator...252 Examining the four processes in a vaporcompression refrigerator...253 Analyzing the cycle with refrigerant property tables...256 Calculating the vapor-compression refrigerator coefficient of performance...258 Calculating vapor-compression refrigerator irreversibility...259 Warming Up with Heat Pumps...260 Examining the four processes in a heat pump...260 Analyzing a heat pump...262 Calculating the heat pump coefficient of performance...262 Calculating heat pump irreversibility...263
xiv Thermodynamics For Dummies Part IV: Handling Thermodynamic Relationships, Reactions, and Mixtures... 265 Chapter 14: Understanding the Behavior of Real Gases...........267 Deviating from Ideal-Gas Behavior: Real-Gas Behavior...268 Determining Properties with the Compressibility Factor...270 Using reduced temperature and pressure...272 Using pseudo-reduced volume...273 Finding Pressure with van der Waals...274 Chapter 15: Mixing Gases That Don t React with Each Other......277 Determining Thermodynamic Properties for a Mixture of Gases...278 Using mass and molar fractions for gas mixtures...278 Finding properties of a gas mixture...280 Getting the Compressibility Factor for Real-Gas Mixtures...282 Making assumptions for mixture compressibility factors...283 Finding compressibility factors with Amagat s law...284 Finding compressibility factors with Dalton s law...285 Calculating compressibility factors with Kay s Rule...287 Working with Psychrometrics: Air and Water Vapor Mixtures...288 Finding the wet-bulb temperature with a sling psychrometer...289 It s muggy out there: Calculating specific and relative humidity...290 My glasses are fogging up: Defining the dew point...292 Working out problems with temperature and humidity...293 Using the psychrometric chart...294 Making Life Comfortable with Air Conditioning...297 Heating and humidifying the air...297 Cooling and dehumidifying the air...300 Chapter 16: Burning Up with Combustion.......................303 Forming Combustion Reaction Equations...304 Figuring out how much air you need: Writing stoichiometric reaction equations...305 Accounting for excess air in combustion...306 Defining Combustion-Related Thermodynamic Properties...307 Enthalpy of formation...308 Enthalpy of combustion...310 Using the First Law of Thermodynamics on Steady-Flow Combustion Systems...314 Analyzing an Example Steady-Flow System...315 Using the First Law of Thermodynamics on Closed Combustion Systems...318 Analyzing an Example Closed System...318
Table of Contents xv Ouch! That s Hot: Determining the Adiabatic Flame Temperature...321 Figuring Out an Example Adiabatic Flame Temperature...322 Part V: The Part of Tens... 325 Chapter 17: Ten Famous Names in Thermodynamics.............327 George Brayton...327 Nicolas Léonard Sadi Carnot...328 Anders Celsius...328 Rudolf Diesel...328 Daniel Gabriel Fahrenheit...329 James Prescott Joule...329 Nikolaus August Otto...329 William John Macquorn Rankine...330 William Thomson or Lord Kelvin...330 James Watt...330 Chapter 18: Ten More Cycles of Note...........................331 Two-Stroke Engines...331 Wankel Engines...332 The Stirling Cycle...333 The Ericsson Cycle...334 The Atkinson Cycle...335 The Miller Cycle...335 The Absorption Cycle...336 The Einstein Cycle...337 Combined-Cycle Engines...338 Binary Vapor Cycles...339 Appendix... 341 Index... 351
xvi Thermodynamics For Dummies