Continue Ideal Rankine Power Cycle Define ideal Rankine power cycle: .Neglect the finite temperature difference of heat exchanger →△THx=0,TBoiler=TH and Tcond=TL Isentropic expansion and pumping processes →S1=S2andS3=s4 Difference between ideal Rankine and Carnot power cycle: ·①Instead of isentropic compression from3→4(Carnot),itis isentropic pumping from saturated liquid (3)to subcooled liquid (4)(Rankine)due to the use of actual working fluid (water/steam) ·②Quality at turbine exit not too low> Cooling curve for the products of combustion 3Rankine:Non-isothermal heat addition,good the combustion heat ·④Carnot:two-phase pump is hard to handle 上游通大学 Wednesday,April 26,2017 9 SHANGHAI JIAO TONG UNIVERSITYWednesday, April 26, 2017 9 Continue Ideal Rankine Power Cycle Define ideal Rankine power cycle: • Neglect the finite temperature difference of heat exchanger  ∆THX = 0, TBoiler = TH and TCond = TL • Isentropic expansion and pumping processes  s1=s2 and s3=s4 Difference between ideal Rankine and Carnot power cycle: • ① Instead of isentropic compression from 3  4 (Carnot), it is isentropic pumping from saturated liquid (3) to subcooled liquid (4) (Rankine) due to the use of actual working fluid (water/ steam) • ② Quality at turbine exit not too low • ③ Rankine: Non-isothermal heat addition, good for using the combustion heat • ④ Carnot: two-phase pump is hard to handle