T2pTp?2 2?2 T3p3T3p1 S2?S1?CPlnV2p?CVln2 V1p1在1?2等温过程中 p1V1?p2V2 所以 S2?S1?CPlnV2VCV2lnV2Vln?RV?Rln21V111?4?2熵变
S4dQ2d2?S1??1T??Q4T S2?S1?0??T2CpdTTT?ClnT24pT?CTpln1 4T41?4绝热过程
T1V??1??1T1V??141?T4V4T???1 4V1p?V41V1?p?4V4,?(p1)1/??(p1)1/?V 1p4p2在1?2等温过程中 p1V1?p2V2
V4?(p1)1/??(p1)1/??(V2)1/?V 1p4p2V1T??11?(V2?T)
4V1ST12?S1?CPlnT?C??1V2P?lnV?Rln2 41
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