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moist • Symbols • described, 288 ρ. See density dew point of, 292–294, 296–297 ε (effectiveness), 185–186, 189 of, 295–297 humidity of, 290–292, 293–294, 295–297 ηP (propulsive effi ciency), 192 φ (relative humidity), 290–292 as nonreactive gas mixture, 278 water vapor in, amount of, 289 ηII (second-law effi ciency), 162–164 ω (specifi c humidity), 290–292 molecular mass of, 55 γ (specifi c weight), 22 thermodynamic properties of, 349 η . See thermal effi ciency treating as pure substance, 277 th air conditioning systems. See also refrigeration systems cooling and dehumidifying, 300–302 • A • exchangers in, 102 heating and humidifying, 297–300 A. See availability throttling valves in, 104 a (acceleration), 18, 62–63 air-fuel ratio (AFR), 312–314, 320 absolute scale, 19 aluminum absolute zero temperature contracting upon freezing, 40 indicating zero energy, 10, 20 thermodynamic properties of, 349 zero at, 37–38, 124 Amagat’s law, 283, 284–285 absorption cycle, 336–337 ammonia acceleration (a), 18, 62–63 absorption cycle using, 336 acceleration of gravity (g), 17 critical point properties of, 269, 350 acetylene, enthalpy of formation for, 309 Einstein cycle using, 337 adiabatic fl ame temperature, 321–324 thermodynamic properties of, 349 , 31, 65–66, 86–88, 139, apparent ideal-gas constant (R ), 281–282 169, 199, 224 m apparent molar mass (M ), 281–282 AFR (air-fuel ratio), 312–314, 320 m argon air. See also air-conditioning gas constant of, 55 systems; atmosphere molecular mass of, 55 in combustion reactions, 305–307 , 335 critical point properties of, 269, 350 COPYRIGHTEDatm (atmospheres), MATERIAL 40 dehumidifying, 300–302 atmosphere. See also air; atm dry, 288 boundary against, 148 gas constant of, 55 as dead state environment, 146 heating, 297–300 as heat exchanger, in , 172 humidifying, 297–300 as natural thermal reservoir, 113 as , 268 pressure of, at sea level, 18 ideal-gas properties of, 341

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attractive (or binding) forces, 25–26, 267 regeneration used with, 184–186 availability (A) thermal effi ciency of, 181–182 balancing in a system, 156–159 Brayton/Rankine combined cycle, 338 in closed systems, 147–151 Btu (British thermal unit), 24, 157 decrease in energy availability principle, 112, 159 described, 114, 145, 146 • C • in open systems c. See specifi c heat balancing, 156–159 C (Celsius scale), 20, 21, 328 with steady fl ow, 151–154 calories, 24 with transient fl ow, 154–156 carbon dioxide (CO2) transferring critical point properties of, 269, 350 using heat transfer, 158 enthalpy of formation for, 309 using mass fl ow, 158–159 formed in combustion reactions, using work, 157–158 278, 304, 306 units for, 157 gas constant of, 55 molecular mass of, 55 thermodynamic properties of, 349 • B • carbon monoxide back work ratio, 174, 189, 228 enthalpy of formation for, 309 benzene, enthalpy of formation for, 309 formed in combustion reactions, 278, 306 binary vapor cycles, 339 binding (or attractive) forces, 25–26, 267 coeffi cient of performance for, 249–250, 258 boilers described, 168–169, 328 described, 68–70 processes in, 169–170 enthalpy (H) for, 52–53, 69–70 thermal effi ciency of, 171 heat transfer rate for, 68–70 in T-s diagrams, 130 mass fl ow rate for, 69 Celsius, Anders (scientist), 328 in , 222 Celsius (°C) scale, 20, 21, 328 bomb calorimeter, 318 centigrade scale, 328. See also boundary, 30 Celsius (°C) scale boundary work, 63–67, 131, 148, 151 chemical energy Brayton, George (mechanical engineer), 327 in combustion reactions, 307, 314 Brayton cycle. See also reverse described, 11, 26 Brayton cycle Clausius statement, 118–120 actual compared to ideal, 190–191 closed systems analyzing availability in, 147–151 constant specifi c heat method, combustion reactions in, 314, 318–320 175–178, 180–181 conservation of energy in, 78–80 variable specifi c heat method, conservation of mass in, 77–78 175, 178–181 described, 78, 92 described, 172, 327 with ideal gases intercooling and reheating used with, in adiabatic processes, 86–88 186–189 in constant-pressure processes, 82–84 irreversibility of, 182–183 in constant-temperature processes, 85–86 processes in, 173–175 in constant- processes, 81–82

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irreversibility in, 160–161 isentropic, 170 with liquids, 88–90 isothermal, 170 with solids, 88–90 condensers

CO2. See carbon dioxide described, 70–71, 120, 127 coeffi cient of performance (COP) entropy increased by, 126–127 described, 120–121 in Rankine cycle, 222 for heat pumps, 262–263 conservation of energy. See also fi rst law for reverse Brayton cycle, 249–250 of thermodynamics for vapor compression system, 258 acceptance of, 329 cogeneration, 118 in closed systems, 78–80 cold-air standard assumption, 202 with , 101–102 combined cycle, 118 described, 35–36 combined-cycle heat , 338 for ideal gases, 81–88 combustion reactions for liquids, 88–90 adiabatic fl ame temperature of, 321–324 mass and energy, balancing, 94–95 air in, 305–307 for solids, 88–90 air-fuel ratio, 312–314 with steady state processes, 95–97 in closed systems, 314, 318–320 with transient processes, 108 described, 13–14, 303–305 conservation of mass enthalpy of combustion for, 310–314 in closed systems, 77–78 enthalpy of formation for, 308–309 mass and energy, balancing, 94–95 general combustion reaction equation in open systems, 91–94 for, 305–307 constant specifi c heat heating value of fuel, 312 in Brayton cycle, 175–178, 180–181 hydrocarbons as fuels for, 304 in , 213–216 ideal-gas properties of combustion entropy for, 137, 138–139, 140–141 gases, 348 in , 202–204, 207 in open systems, 314, 315–317 in reverse Brayton cycle, 247–249 products of, 304 constant specifi c volume, of moist air, reactants in, 304 295–297 reference state for, 307 constant-enthalpy (isenthalpic) process in steady-fl ow systems, 314–317 described, 31 compressed liquid in heat pumps, 262 changing to saturated liquid, 46–47 in vapor compression system, 255 described, 43, 224 constant-entropy (isentropic) process entropy of, 132 in Brayton cycle, 173 linear interpolation used with, 51 calculating availability for, 149–151 compressed liquid water properties, 342 calculating entropy for, 139–143 chart, 267, 283–284 in Carnot cycle, 169, 170 compressibility factor (Z) described, 31 in ideal-gas law, 270–273, 282–288 entropy unchanged by, 126 for real-gas mixtures, 282–288 in heat pumps, 261 compression ratio, 200 in Rankine cycle, 224, 225 compressors in reverse Brayton cycle, 246, 247 described, 100–102 in vapor compression system, 254 effi ciency of, 190

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constant-pressure (isobaric) process density (ρ) in Brayton cycle, 173, 174 compressibility factor with, 270–271 described, 31 described, 21–22 in heat pumps, 261, 262 determining ideal gases from, 55, 267 ideal gases in, 82–84 units for, 21 with piston-cylinder device, 65 dew point, 292–293 in reverse Brayton cycle, 246, 247 Diesel, Rudolf (inventor and engineer), 328 in vapor compression system, 254, 255 diesel cycle constant-pressure specifi c heat, 28, 280–282 analyzing, 213–218 constant-temperature (isothermal) process described, 212, 328 calculating entropy for, 128–130 effi ciency of, 218–219 in Carnot cycle, 169 irreversibility of, 219–220 described, 31 processes of, 212–213 with ideal gases, 85–86 diesel fuel with piston-cylinder device, 65 analyzing combustion process using, constant-volume (isochoric or isometric) 318–320 process enthalpy of combustion for, 311 described, 31 enthalpy of formation for, 309 ideal gases in, 81–82 diffusers, 98–100 with piston-cylinder device, 66 dry ice, sublimation of, 26, 41 constant-volume specifi c heat, 28, 280–282 dry-bulb temperature, 289, 293–294, 295 conventions used in this book, 2, 5–6 cooling the air. See air conditioning systems COP (coeffi cient of performance) • E • described, 120–121 E. See energy for heat pumps, 262–263 effectiveness (ε), 185–186, 189 for reverse Brayton cycle, 249–250 Einstein cycle, 337 for vapor compression system, 258 endothermic reaction, 308 copper energy (E) contracting upon freezing, 40 availability of thermodynamic properties of, 349 balancing in a system, 156–159 critical point in closed systems, 147–151 described, 42–43, 224, 268–269 decrease in energy availability principle, properties of various materials, 269, 350 112, 159 cycles. See also specifi c cycles decrease in, proportional to increase in described, 32–33 entropy, 159 incomplete, 34 described, 114, 145, 146 in open systems with steady fl ow, 151–154 • D • in open systems with transient fl ow, Dalton’s law, 283, 285–287 154–156 dead state, 146 transferring using heat transfer, 158 decrease in energy availability principle, transferring using mass fl ow, 158–159 112, 159 transferring using work, 157–158 dehumidifying the air, 300–302 units for, 157 balancing with mass, 94–95

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chemical energy of formation, 308–309 in combustion reactions, 307, 314 for gas mixtures, 280–282 described, 11, 26 of moist air, 293–294, 295–297 conservation of. See conservation of vaporization, 48 of energy entropy (S). See also ; described, 22–23 second law of thermodynamics direction of movement by, 10, 36–37 balancing in a system, 143–144 forms taken by, 10–12 calculating for a system, 126–131 (U) described, 29, 123–126 described, 11–12, 25–26, 131 enthalpy related to, 131 for gas mixtures, 280–282 fl ow work related to, 131 as microscopic energy, 23 for gas mixtures, 280–282 internally reversible change in, 125 from heat transfer, 125–126, 129, 130, kinetic energy, 11, 24–25 143–144 latent energy, 26 for ideal gases, 136–139 limits on, in second law of “increase in entropy” principle, 4, 159 thermodynamics, 112 for isentropic processes, 139–143 macroscopic, 23 for liquids, 132–135 microscopic, 23 at macroscopic level, 125–126 none, implying no temperature also, 10 at microscopic level, 124 nuclear energy, 26 pressure affecting, 29 potential energy, 11, 25 for pure substances, 131–134 quality of, 23, 36–37, 49, 112 for solids, 134–135 sensible, 25 T-ds relationships for, 130–131 total energy, calculating, 26–27 temperature affecting, 29 transferring T-s diagram for, 128–130 as heat transfer, 23, 35 unchanged by isentropic processes, 126 as mass transfer, 23, 35 units for, 125 as work, 23, 35 zero types of, 23–27 below reference temperature, 132 units for, 24 indicating absolute zero temperature, energy balance, 35–36, 80 37–38, 124

energy conservation. See conservation entropy generation (Sgen), 125–126 of energy environment. See atmosphere; displacement, 200 surroundings engines. See specifi c types of engines equations of state English unit system, 17 described, 54, 267 enthalpy (H). See also ideal-gas law for boilers, 52–53, 69–70 compressibility factor with, 270–273, of combustion or reaction, 310–314 282–288 for condensers, 71 described, 54–56, 81 described, 27 van der Waals, 274–276 entropy related to, 131 Ericsson cycle, 334 for evaporators, 72–73

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ethanol ft3/lbm (cubic feet per pound-mass), 22 critical point properties of, 269, 350 FWH (feedwater heater), 234 enthalpy of combustion for, 311 thermodynamic properties of, 349 evaporators, 71–73, 119 • G • excess air, in combustion, 306–307 g (acceleration of gravity), 17 exergy. See availability (A); quality (x) gas constant (R), 28, 54–55 exothermic reaction, 308 gas refrigeration cycle, 245. See also extensive properties, 17 reverse Brayton cycle engines. See also Brayton cycle; ; jet engines • F • described, 115, 167 F. See force effi ciency of, 190–191 F (Fahrenheit scale), 20, 21, 329 gases. See also equations of state; phases Fahrenheit (°F) scale, 20, 21, 329 “g” subscript used for, 26 Fahrenheit, Daniel Gabriel, 329 generalized compressibility chart for, feedwater, 68 267, 283–284 feedwater heater (FWH), 234 ideal gases fi rst law of thermodynamics in adiabatic processes, 86–88 availability balance of open systems, air as, 268 156–159 in Brayton cycle, 268 in Brayton cycle, 175–178 conservation of energy for, 81–88 in closed systems, 78–90 in constant-pressure processes, 82–84 described, 35–36 in constant-temperature processes, with ideal-gas processes, 81–88 85–86 in open systems, 91–109 in constant-volume processes, 81–82 in Otto cycle, 202–207 described, 81 perpetual motion machines violating, determining, 268–270 121–122 entropy (S) for, 136–139 in steady-fl ow combustion systems, identifying, 55 314–317 low density indicating, 55, 267 fl ames, adiabatic temperature of, 321–324 in Otto cycle, 268

fl ow work (wfl ow), 94–95, 131 water vapor as, 269 fl uorocarbons, in refrigerants, 252 ideal-gas law for force (F) compressibility factor with, 270–273, calculating, 59–61 282–288 described, 18, 58 described, 54–56, 81 units for, 60 nonreactive mixtures four-stroke reciprocating engines, apparent ideal-gas constant for, 281–282 198–201 apparent molar mass for, 281–282 Freon, 252 compressibility factors for, 282–288 friction described, 13–14, 277–278 described, 11–12 mass fractions for, 279–280 as , 169, 182, 190, moist air as, 278 208, 250 molar fractions for, 279–280 properties of, 280–282

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pseudo-reduced volume for, 283–284 Kelvin-Planck statement regarding, 115–116 real gases processes used by, 12–13 compressibility factor with, 270–272 second-law effi ciency of, 162, 163–164 determining, 268–270 thermal effi ciency of, 117 high density indicating, 267 waste heat from, uses for, 118 pseudo-reduced specifi c volume with, heat exchangers. See also condensers; 273–274 evaporators; regeneration in Rankine cycle, 268, 269 atmosphere as, in Brayton cycle, 172 reduced temperature and pressure with, in Brayton cycle, 172, 173–174, 186 272–273 described, 68, 102–104 van der Waals for, in FWH, 235 274–276 in reverse Brayton cycle, 245, 246, 247 reduced pressure for, 271–273, 283–284 in vapor compression system, 253, 260 reduced temperature for, 271–273, heat pumps. See also refrigeration systems 283–284 analyzing, 262 specifi c heat of, 28–29 coeffi cient of performance (COP), 262–263 specifi c volume of, 272–273 described, 118, 260 thermodynamic properties of various irreversibility of, 263–264 gases, 349 processes in, 260–262 gasoline. See also combustion reactions; heat sink, 37 Otto cycle heat sink reservoir, 113, 116, 118 air-fuel ratio for, 312–314 heat source, 37 composition of, 307 heat source reservoir, 113, 115 enthalpy of combustion for, 311 heat transfer (Q). See also adiabatic general combustion reaction equation, process; second law of 305–307 thermodynamics generalized compressibility chart, availability transferred using, 158 267, 283–284 described, 23, 68 Gibbs equations entropy associated with, 125–126, 129, described, 130–131 130, 143–144 for ideal gases, 136–137 internally reversible change in energy for liquids and solids, 134–135 from, 125 gravity none, with thermal equilibrium, 34–35 as source of potential energy, 11 units for, 68 specifi c gravity, 22 heat transfer rate ( ) weight determined by, 17 for boilers, 68–70 for condensers, 71 in conservation of energy rate equation, 80 • H • for evaporators, 71–73 H. See enthalpy heating the air, 297–300 h. See latent heat heating value of fuel, 312 heat, specifi c. See specifi c heat helium heat engine. See also Carnot cycle gas constant of, 55 boilers, 68–70 molecular mass of, 55 described, 12–13, 57, 114–115

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humidity internal combustion engines, 115. See also calculating, 293–294 combustion reactions; heat engine dehumidifying the air, 300–302 internal energy (U) described, 290–292 described, 11–12, 25–26, 131 determining with psychometric chart, for gas mixtures, 280–282 295–297 as microscopic energy, 23 humidifying the air, 297–300 internally reversible process, 125, 127–128, hydrogen 129–130, 144 gas constant of, 55 interpolation molecular mass of, 55 linear, 51–52 with two variables, 52–53 iron • I • contracting upon freezing, 40 I. See irreversibility oxidizing, 303 ice thermodynamic properties of, 349 cooling work performed by, 89–90 irreversibility (I) dry ice, 26, 41 of Brayton cycle, 182–183 sublimation of, 41 causes of, 125, 146, 157, 159, 161, 182, thermodynamic properties of, 349 208–209, 250 icons used in this book, 5–6 described, 146, 160–162 ideal gases of diesel cycle, 219–220 in adiabatic processes, 86–88 entropy resulting from, 125 air as, 268 gas expansion as, 125 in Brayton cycle, 268 of heat pumps, 263–264 conservation of energy for, 81–88 of Otto cycle, 208–211 in constant-pressure processes, 82–84 of Rankine cycle, 228–230 in constant-temperature processes, 85–86 of reverse Brayton cycle, 250–252 in constant-volume processes, 81–82 of vapor compression system, 259–260 described, 81 isenthalpic (constant-enthalpy) process determining, 268–270 described, 31 entropy (S) for, 136–139 in heat pumps, 262 identifying, 55 in vapor compression system, 255 low density indicating, 55, 267 isentropic (constant-entropy) process in Otto cycle, 268 in Brayton cycle, 173 water vapor as, 269 calculating availability for, 149–151 ideal-gas law (equation of state) calculating entropy for, 139–143 compressibility factor with, 270–273, in Carnot cycle, 169, 170 282–288 described, 31 described, 54–56, 81 entropy unchanged by, 126 ideal-gas properties in heat pumps, 261 of air, 341 in Rankine cycle, 224, 225 of combustion gases, 348 in reverse Brayton cycle, 246, 247 intensive properties, 17 in vapor compression system, 254 intercooling and reheating, in Brayton isobaric (constant-pressure) process cycle, 186–189 in Brayton cycle, 173, 174 described, 31

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in heat pumps, 261, 262 ideal gases in, 82–84 • L • with piston-cylinder device, 65 latent energy, 26 in reverse Brayton cycle, 246, 247 latent heat (h) in vapor compression system, 254, 255 of fusion, 26 isochoric or isometric (constant-volume) of sublimation, 26 process of vaporization, 26, 48 described, 31 . See fi rst law ideal gases in, 81–82 of thermodynamics; ideal-gas law; with piston-cylinder device, 66 second law of thermodynamics; third isothermal (constant-temperature) process law of thermodynamics; zeroth law of calculating entropy for, 128–130 thermodynamics in Carnot cycle, 169 lbf (pounds-force), 17 described, 31 lbf/ft3 (pounds-force per cubic foot), 22 with ideal gases, 85–86 lbm (pound mass), 17 with piston-cylinder device, 65 lbm/ft3 (pound-mass per cubic foot), 21 linear interpolation, 51–52 • J • liquids. See also phases; water changing to vapor, 45–50 J (joules), 24 conservation of energy for, 88–90 jet engines evaporating or condensing, latent energy actual, analyzing, 194–195 for, 26 described, 191–192 “f” subscript used for, 26 ideal, analyzing, 192–194 freezing or melting, latent energy for, 26 Joule, James Prescott (physicist), 329 R-134a liquid-vapor properties, 346 specifi c heat of, 27–28 thermodynamic properties of various • K • liquids, 349 k. See spring constant; specifi c heat ratio liquid-vapor dome Kay’s rule, 283, 287–288 described, 42–43, 224, 268 KE (kinetic energy), 11, 24–25 in P-v diagram, 44 Kelvin (K) scale, 20, 21 quality in, 49–50 Kelvin, Lord (William Thomson), 329, 330 Kelvin-Planck statement, 115–116 kerosene, thermodynamic properties of, 349 • M • kg (kilogram), 17 m. See mass kg/m3 (kilograms per cubic meter), 21 . See mass fl ow rate kg/sec (kilograms per second), 78 M. See molecular mass; molecular weight kinetic energy (KE), 11, 24–25 m3/kg (cubic meters per kilogram), 22 kJ (kilojoules), 58, 157 m3/sec (cubic meters per second), 92 kJ/kg · K (kilojoles per kilogram per Mm (apparent molar mass), 281–282 Kelvin), 27, 125 macroscopic energy, 23 kN (kilonewtons), 60 mass (m). See also conservation of mass; kPa (kilopascal), 18 extensive properties kW (kilowatts), 58 balancing with energy, 94–95 described, 17–18

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mass (m) (continued) units for, 17 • N • mass fl ow N (newton), 17 availability transferred using, 158–159 nitrogen entropy transferred using, 143, 144 critical point properties of, 350 none, in or out of closed system, 78, 144 gas constant of, 55 mass fl ow rate ( ) molecular mass of, 55 in a boiler, 69 nitromethane, 306, 311, 312–314 in compressors, 101 Nm (newton-meters), 61 conservation of mass determining, 78, 92 N/m3 (newtons per cubic meter), 22 in heat exchangers, 103–104 nonreactive gas mixtures in a jet engine, 93 apparent ideal-gas constant for, 281–282 in nozzles and diffusers, 99 apparent molar mass for, 281–282 in an open system, 92 compressibility factors for, 282–288 in an open system with steady fl ow, 95–96 described, 13–14, 277–278 in Rankine cycle with FWH, 237–238 mass fractions for, 279–280 for transient processes, 107 moist air as, 278 units for, 69, 78 molar fractions for, 279–280 mass fraction (mf), 279–280, 281 properties of, 280–282 mass transfer, 23, 78, 156. See also nozzles, 98–100 conservation of mass nuclear energy, 26 matter, forms taken by, 10 mean effective pressure (MEP), 211 methane • O • enthalpy of combustion for, 311 octane enthalpy of formation for, 309 composition of, 306 methanol compression ratio of engine related to, 207 critical point properties of, 269, 350 enthalpy of combustion for, 311–312 thermodynamic properties of, 349 enthalpy of formation for, 309 metric system. See SI unit system excess air with, 306–307 mf (mass fraction), 279–280, 281 thermodynamic properties of, 349 microscopic energy, 23 oil, contracting upon freezing, 40 , 335–336 open systems moist air availability for described, 288 balancing, 156–159 dew point of, 292–294, 296–297 with steady fl ow, 151–154 enthalpy of, 295–297 with transient fl ow, 154–156 humidity of, 290–292, 293–294, 295–297 balancing mass and energy in, 94–95 as nonreactive gas mixture, 278 combustion reactions in, 314, 315–317 water vapor in, amount of, 289 with compressors, 100–102 molar fraction (y), 279–280, 281 conservation of mass in, 91–94 molecular attractive forces, 25–26, 267 described, 78, 92 molecular mass (M), 54–55 with diffusers, 98–100 molecular weight (M), 55, 304 with heat exchangers, 102–104 moving boundary work, 63–67 irreversibility in, 161 mass fl ow rate for, 92, 95–96

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with nozzles, 98–100 for compressing and heating air, 138 with pumps, 100–102 for cooling processes, 134 in steady state processes, 95–97 described, 128–130 with throttling valves, 104–106 for diesel cycle, 213 in transient processes, 106–109 for ideal turbine, 141 with turbines, 100–102 for ideal-gas law, 268 Otto, Nikolaus August (inventor), 329 for Otto cycle, 199 Otto cycle for Rankine cycle, 224, 231, 235, 240 analyzing, 202–207 for reverse Brayton cycle, 246 described, 201, 329 for throttling valves, 105 effi ciency of, 208 for engine cycle, 193 irreversibility of, 208–211 for vapor-compression refrigeration P-v diagram for, 198 cycle, 254 oxygen. See also air; atmosphere T-v diagram, 42–44, 45 critical point properties of, 350 phases, 39–41 gas constant of, 55 piston-cylinder device, 63–67. See also molecular mass of, 55 reciprocating engines , 66 potential energy (PE), 11, 25 • P • power ( ), 58, 62, 63, 80, 117, 192, 227. P. See pressure See also force (F); work (W) P’ (pseudocritical pressure), 287–288 pressure (P). See also ; c second law of thermodynamics; stress PR (reduced pressure), 271–273, 283–284 Pa (Pascal), 18 absolute pressure scale, 19 paraffi n, contracting upon freezing, 40 of atmosphere at sea level, 18 paths, 30–32. See also processes calculating with ideal-gas law, 54–56 PE (potential energy), 11, 25 described, 18–19 perpetual motion machines, 121–122 direction of, 112 phase changes, 45–46 entropy affected by, 29 phase diagram gauge pressure scale, 19 described, 41–42 increasing, entropy decreased by, 124 P-v diagram mean effective pressure (MEP), 211 for Atkinson cycle, 335 pseudocritical pressure, 287–288 for Brayton cycle, 175 reduced pressure, 271–273, 283–284 for constant-pressure processes, 83 relative pressure, 142 for constant-temperature processes, 86 saturation pressure, 46 described, 44–45 units for, 18–19, 40 for diesel cycle, 213 vacuum pressure scale, 19 for Ericsson cycle, 334 pressure-volume-temperature for Miller cycle, 336 relationships. See P-v-T relationships for Otto cycle, 198, 199 processes. See also specifi c processes; for reversible-adiabatic processes, 87 second law of thermodynamics for , 334 connecting, into a cycle, 32–33 T-s diagram described, 15, 29–30 for Brayton cycle, 175, 185, 187, 191 direction of movement by, 112 for Carnot cycle, 170

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processes (continued) for Miller cycle, 336 ending point, 3 for Otto cycle, 198, 199 path for, 30–32 for reversible-adiabatic processes, 87 possibility of, 4, 111, 115, 119, 161, 168 for Stirling cycle, 334 starting point, 3 P-v-T (pressure-volume-temperature) propane relationships. See also equations critical point properties of, 269, 350 of state enthalpy of combustion for, 311 for adiabatic processes, 86–88 enthalpy of formation for, 309 for constant-pressure processes, 82–84 properties, 16–29. See also specifi c for constant-temperature processes, properties 85–86 property tables for constant-volume processes, 81–82 interpolation with two variables using, described, 40–41, 81 52–53 linear interpolation using, 51–52 listed, 341–350 • Q •

propulsive effi ciency (ηP), 192 Q. See heat transfer propulsive power (W ), 192 P . See heat transfer rate propylene, enthalpy of formation for, 309 quality (x), 23, 36–37, 49, 112 pseudocritical pressure (P’c), 287–288 pseudocritical temperature (T’c), 287–288 pseudo-reduced specifi c volume, 273–274 • R • pseudo-reduced volume (v ), 283–284 R (gas constant), 28, 54–55 psi (pounds-force per square inch), 19 R R (Rankine scale), 20, 21 psia (pounds-force per square inch R (apparent ideal-gas constant), 281–282 absolute), 19 m psig (pounds-force per square inch R. See universal gas constant gauge), 19 R-134a psychometric chart, 294–297 critical point properties of, 269, 350 psychrometrics liquid-vapor properties, 346 charting, 294–297 superheated properties, 347 described, 288 thermodynamic properties of, 349 dew point, determining, 292–293 Rankine (R) scale, 20, 21 humidity, calculating, 289–292, 293–294 Rankine, William John Macquorn (engineer sling psychrometer, 289 and physicist), 330 pumps Rankine cycle. See also Brayton/Rankine described, 100–102 combined cycle in Rankine cycle, 222 actual, analyzing, 239–242 P-v diagram described, 221–223, 330 for Atkinson cycle, 335 effi ciency of, 228 for Brayton cycle, 175 ideal, analyzing, 226–228 for constant-pressure processes, 83 irreversibility of, 228–230 for constant-temperature processes, 86 processes in, 223–225 described, 44–45 regeneration used with, 233–239 for diesel cycle, 213 reheating used with, 230–233 for Ericsson cycle, 334 Ready Motor, 327

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real gases described, 243, 252–253 compressibility factor with, 270–272 irreversibility of, 259–260 determining, 268–270 processes in, 253–255 high density indicating, 267 regeneration pseudo-reduced specifi c volume with, in Brayton cycle, 184–186 273–274 in Rankine cycle, 233–239 in Rankine cycle, 268, 269 reheating reduced temperature and pressure with, in Brayton cycle, 186–189 272–273 in Rankine cycle, 230–233 van der Waals equation of state for, relative humidity (φ), 290–292 274–276 relative pressure, 142 real process, 125 relative volume, 142–143 reciprocating engines reservoirs, thermal. See thermal reservoirs compression ratio, 200 reverse Brayton cycle described, 197–201 analyzing, 247–249 diesel cycle for, 212–220 coeffi cient of performance (COP), 249–250 engine displacement, 200 described, 243, 244–245 four-stroke, 198–201 irreversibility of, 250–252 mean effective pressure of, 211 processes in, 245–247 Otto cycle for, 198, 201–211 reversible cycle, Carnot cycle as, 168–169 two-stroke, 198, 331–332 reversible path, 31

reduced pressure (PR), 271–273, 283–284 reversible work (wrev), 146, 160–162 reduced temperature (TR), 283–284 reversible-adiabatic process, 65–66, 86–88, reference state, for combustion, 307 139, 169, 199, 224 refrigerant, 252 refrigeration systems absorption cycle, 336–337 • S • air conditioning, 118, 300–302 S. See entropy Carnot refrigerator, 249–250, 258 Sgen (entropy generation), 125–126 Clausius statement for, 118–120 Sadi Carnot, Nicolas Léonard (engineer), 328 coeffi cient of performance (COP) of, saturated liquid, 46, 47–50 120–121 saturated liquid line, 42 condensers, 70–71 saturated R-134a liquid-vapor properties, described, 13, 57, 68, 118–120, 243–244 346 Einstein cycle, 337 saturated vapor, 47–48, 50 evaporators, 71–73 saturated vapor line, 42 reverse Brayton cycle saturated water liquid-vapor properties, analyzing, 247–249 343–344 coeffi cient of performance (COP), saturation pressure, 46 249–250 saturation temperature, 46, 222 described, 243, 244–245 scavenging, 331 irreversibility of, 250–252 second law of thermodynamics. See also processes in, 245–247 availability (A); quality (x) second-law effi ciency of, 163 Clausius statement of, 118–120 vapor compression system described, 4, 36–37, 111–112, 145 analyzing, 256–258 heat engines using, 114–118 coeffi cient of performance (COP), 258

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second law of thermodynamics (continued) specifi c weight (γ), 22 Kelvin-Planck statement of, 115–116 spring constant (k), 59–61 perpetual motion machines violating, 122 springs, 59–61 refrigeration systems using, 118–122 standard atmospheric pressure, 19 T-s diagrams for, 128–130 state, 29, 31–32

second-law effi ciency (ηII), 162–164 state postulate, 32 sensible energy, 25 steady state process, 95–97 SG (specifi c gravity), 22 steady-fl ow systems, 314–317 shafts, 61–62 steam, superheated, 50, 345 SI (Système Internationale) unit system, 17 steam generators. See boilers sling psychrometer, 289, 293–294 steam power plants, 115. See also heat solids. See also phases engine conservation of energy for, 88–90 steam turbine engines. See Rankine cycle evaporating to gas, latent energy for, 26 steel, thermodynamic properties of, 349 “i” subscript used for, 26 Stirling cycle, 333–334 specifi c heat of, 27–28 stoichiometric reactions, 305 thermodynamic properties of various stress, 18 solids, 349 subcooled-liquid. See compressed liquid specifi c gravity (SG), 22 subcritical steam generator, 225 specifi c heat (c) sublimation, 41 constant supercritical fl uid, 42, 268 in Brayton cycle, 175–178, 180–181 supercritical steam generator, 225 in diesel cycle, 213–216 superheated R-134a properties, 347 entropy for, 137, 138–139, 140–141 superheated steam, 50, 345 in Otto cycle, 202–204, 207 superheated vapor, 50 in reverse Brayton cycle, 247–249 surroundings. See also atmosphere constant pressure, 280–282 described, 29–30 constant volume, 280–282 entropy increasing in, 112, 126–127, 159 described, 16, 27–29 Système Internationale unit system (SI unit variable system), 17 in Brayton cycle, 175, 178–181 systems. See also closed systems; in diesel cycle, 216–218 open systems entropy for, 137, 139, 142–143 availability balance of, 156–159 in Otto cycle, 202, 204–207 described, 29, 77–78, 91–92 specifi c , 16 energy balance of, 35–36 specifi c heat ratio (k), 28–29 specifi c humidity (ω), 290–292 specifi c properties, 17 • T • specifi c volume (v) T. See temperature; torque calculating with ideal-gas law, 54–56 T’ (pseudocritical temperature), 287–288 constant, of moist air, 295–297 c TR (reduced temperature), 283–284 described, 22 T-ds relationships, 130–131 of gases, 272–273 temperature (T) pseudo-reduced specifi c volume, 273–274 absolute zero units for, 22 indicating zero energy, 10, 20 indicating zero entropy, 37–38, 124

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calculating with ideal-gas law, 54–56 T-s diagram Celsius (°C) scale, 20–21 for Brayton cycle, 175, 185, 187, 191 constant, in a path. See isothermal for Carnot cycle, 170 process for compressing and heating air, 138 described, 19–21 for cooling processes, 134 as direction of heat transfer, 20 described, 128–130 Fahrenheit (°F) scale, 20–21 for diesel cycle, 213 increasing, entropy increased by, 124 for ideal turbine, 141 Kelvin (K) scale, 20–21 for ideal-gas alw, 268 measuring, zeroth law regarding, 34–35 for Otto cycle, 199 Rankine (R) scale, 20–21 for Rankine cycle, 224, 231, 235, 240 theoretical air, in combustion, 305 for reverse Brayton cycle, 246

thermal effi ciency (ηth) for throttling valves, 105 of Brayton cycle, 181–182 for turbojet engine cycle, 193 of Carnot cycle, 171 for a vapor-compression refrigeration described, 117 cycle, 254 of diesel cycle, 218–219 turbines, 100–102. See also gas turbine of heat engine, 160, 162, 163–164 engines; Rankine cycle of Otto cycle, 208 T-v diagram, 42–44, 45 of Rankine cycle, 228 two-stroke engines, 331–332 thermal energy, 67–70 two-stroke reciprocating engines, 198 thermal equilibrium, 34–35. See also zeroth law of thermodynamics thermal reservoirs, 112–114 • U • thermodynamic laws. See fi rst law of U. See internal energy thermodynamics; ideal-gas law; second United States Customary System, 17 law of thermodynamics; third law units of measurement, 17 of thermodynamics; zeroth law of universal gas constant (R), 54 thermodynamics universe thermodynamic properties, 16–29. See also decrease in availability of, 159 specifi c properties increase in entropy of, 123 thermodynamic property tables as , 9 interpolation with two variables using, 52–53 linear interpolation using, 51–52 • V • listed, 341–350 V. See volume thermodynamics, 9–14 v. See specifi c volume thermometer, zeroth law regarding, 34–35 V (velocity), 24, 62, 92 third law of thermodynamics, 37–38, 124 vR (pseudo-reduced volume), 283–284 Thomson, William (Lord Kelvin), 329, 330 van der Waals equation of state, 274–276 throttling valves, 104–106 vapor thrust force (F), 192 R-134a liquid-vapor properties, 346 torque (T), 61–62 saturated water liquid-vapor properties, transient process, 106–109 343–344 triple point, 42

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vapor compression system superheated steam properties of, 345 analyzing, 256–258 thermodynamic properties of, 349 coeffi cient of performance (COP), 258 water vapor described, 243, 252–253 in air. See moist air irreversibility of, 259–260 enthalpy of formation for, 309 processes in, 253–255 gas constant of, 55 vapor dome, 49–50 as ideal gas, 269 vaporization line, 42 molecular mass of, 55 variable specifi c heat Watt, James (inventor and engineer), 330 in Brayton cycle, 175, 178–181 weight (W), 17–18. See also specifi c weight in diesel cycle, 216–218 wet-bulb temperature, 289, 293–294, 295 entropy for, 137, 139, 142–143 work (W) in Otto cycle, 202, 204–207 for acceleration, 62–63 velocity (V), 24, 62, 92 availability transferred using, 157–158 volume (V). See also specifi c volume; described, 57, 58–59 isochoric or isometric process with piston-cylinder device, 63–67 density calculated from, 21 quality of energy determining, 23 in ideal-gas law, 54, 81 with shafts, 61–62 mass fl ow rate calculated from, 92 with springs, 59–61 · volumetric fl ow rate (V ), 92 units for, 58 • W • • X • W. See weight; work x (quality), 23, 36–37, 49, 112 . See power w (fl ow work), 94–95, 131 fl ow • Y • WP (propulsive power), 192 wrev (reversible work), 146, 160–162 y (molar fraction), 279–280, 281 Wankel engines, 332–333 water compressed liquid water properties, 342 • Z • critical point properties of, 269, 350 Z. See compressibility factor enthalpy of formation for, 309 zeroth law of thermodynamics, 34–35 saturated water liquid-vapor properties, 343–344

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