Polytropic process Ideal gas Any gas/liquid P2 P V 1- (Ideal gas EoS) i.e. pyPVz T Ideal gas n-1 only or P2 上游充通大学 March 25,2019 3 SHANGHAI JIAO TONG UNIVERSITYMarch 25, 2019 3 Polytropic process + Ideal gas 1 1 2 2 1 2 pV p V T T  (Ideal gas EoS) 2 2 2 1 1 1 T p V T pV  1 2 2 1 1 n n T p T p         2 1 1 2 n p V p V        or Ideal gas only 1 1 1 2 1 1 1 2 1 2 2 n n n n n V V V V V V V V              Any gas/liquid 1 2 1 1 2 n T V T V         i.e