Chapter 3 from Moran and Shapiro：3章从莫兰和夏皮罗.ppt

ThermodynamicPropertiesPropertyTable--fromdirectmeasurementEquationofState--anyequationsthatrelatesP,v,andTofasubstanceIdeal-GasEquationofStateAnyrelationamongthepressure,temperature,-knownequationofstateistheideal-gasequationofstate,givenas-=-K=-m3/kmol-k=-m3/kmol-K=-atm/kmol-K=-R=-lbf/lbmol-R=-ft3/lbmol-“Law”isasimpleEquationofStatePercenterrorforapplyingidealgasequationofstatetosteamQuestion…...Underwhatconditionsisitappropriatetoapplytheidealgasequationofstate?IdealGasLawGoodapproximationforP-v-Tbehaviorsofrealgasesatlowdensities(lowpressureandhightemperature).Air,nitrogen,oxygen,hydrogen,helium,argon,neon,carbondioxide,….(<1%error).CompressibilityFactorThedeviationfromideal-pressibilityfactorZ,pressibilityIdealGasZ=1RealGasesZ>1orZ<1