第三章 理想气体的性质与热力过程 下载本文

WT?QT?p1V1lnV2?9.807?105(2?0.1677)ln5?529.4kJ V1过程中热力学能,焓,熵的变化为:

?U1?2?0,?H1?2?0,?S1?2?mRln(2)可逆绝热过程:

V2?0.9238kJ/K V2按可逆绝热过程参数间关系可得:p2s?p1(气体对外所作膨胀功及交换的热量:

v21.4)?1.03bar.v2s?0.8385m3/kg,T2s?301K v1Ws?11(p1V1?p2V2)?mR(T1?T2s)?390.3kJ,Qs?0 k?1k?1过程中热力学能,焓,熵的变化为:

?U1?2s?mcV0(T2S?T1)??390.3kJ,?H1?2s?mcp0(T2s?T1)??546.2kJ,?S1?2s?0