Polytropicprocess（多方过程)：P=CV-nPdv in polytropic process:V=#+1V58+1P.V2-P,VCV-RdV=Pdy1-nn+lFor ideal gas(PV=mRT)mR(T-T)(k))W,=n手11-nForspecial caseof n=1cV-IaV=PVIn(PdV=W
• Polytropic process (多方过程)： • Pdv in polytropic process: • For ideal gas(PV=mRT) • For special case of n=1 11
4-2 energy balance for closed systemsEnergybalanceforanysystemforanyprocessAE,(KJ)Em-EosystomNet energy InansferChiangeinintemal,kinetiebyhea.work.andmaspotenitial,etc.anergiesPer unit massAeeoutsysteminDifferentialformSE-SEour=dEsystem
4-2 energy balance for closed systems • Energy balance for any system for any process • Per unit mass • Differential form 12