Continue two-stage compression with intercooling n-l n- n For dwc=0(minimum work): Px dpx T n-l Pt Savings in work 2t 25 P2 Isentropic Also, P2 T T compression pvk=const T T Px _Isothermal__ compression Polytropic pv=const compression Thus,T2=Tx and Ty =T: pvh=const P1 w-)--)-2 nR >At optimal intermediate pressure,equal work in both stages! 上游通大学 May9,2019 10 SHANGHAI JLAO TONG UNIVERSITYMay 9, 2019 10 Continue two-stage compression with intercooling     n 1 n 1 n n C x x 2 x 1 1 x n 1 n 2 2 x x y 1 2 x y 1 C,1 x 1 2 y C,2 dw T p p For 0 (minimum work): dp T p p p T T Also, p T T Thus, T T and T T : nR nR w T T T T w n 1 n 1                                     At optimal intermediate pressure, equal work in both stages!