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1、第章第三章3-33-3由热力学第一定律Q U WW mgh 450kg9.8m/s 30m 132300J因为绝热 Q=02U 132300J mCVT 4.186103(T220)5kgT2 26.32 CO3-43-4根据热力学第一定律，循环U 0Q W过程1-22-33-44-1Q（kJ)11000-9500W(kJ)0100050E1100-100-950-503-133-13(1)热力学能的变化采用定值比热容U CVT,h CpTMCV77R08.314 29.099kJ/(kmolgK)22MCP(29.099 8.314)kJ/(kmolgK)37.413kJ/(kmolgK)M
2、CV(600900)198.34kJ44.014MCph(600900)255.007kJ44.014U 采用平均比热容CPm60001.040kJ/(kggK),CPm90001.104kJ/(kggK),h 1.1049001.040600 369.6kJU (1.040.0.1889)600(1.1040.1889)900 312.9kJ3-173-17忽略流体动能、位能变化m1h1 m2h2(m1 m2)h3m1T1m2T2120(500273)210(500273)T3m1m2120210582.09K 309.09oC第四章4-24-2（1）由可逆绝热定熵方程得S 011.41mR
3、T1P20.287(273150)0.1W 11()1.4111.87kJ1P1.410.51（2）W U mCV(T2T1)0.7174(300423)88.25kJS CPln(3)T2p3000.1Rln2(0.2870.7174)ln0.287ln 0.117kJ/(kggK)T1p14230.5W RT lnS Rlnp20.5 0.287423ln195.3kJp10.1p1 0.462kJ/(kgK)p2(4)n11RT1 P2n0.2874230.122W 11()67kJn1P210.51TpS CPln2 Rln2 0.462kJ/(kggK)T1p14-64-6（1）T2
4、T1 30oCW mRT lnP0.31 60.287303.15ln 573.5kJP20.1q W 573.5kJ（2）1 P20.11.41.4T2T1 303.15()221.48oC0.3P111W mR(T1T2)60.287(303.15221.48)351.5kJ11.41q 0kJ1（3）1 P20.11.2T2T1 303.15()1.2 252.4oC0.3P111W mR(T1T2)60.287(303.15252.4)436.7kJn11.21nk1.21.4q mCV(T2T1)60.7174(252.4303.15)218.45kJn11.214-74-7ln(P
5、2/Pln(0.12/0.6)1.60941)n 1.3ln(v1/v2)ln(0.236/0.815)1.2393n1n11(Pv Pv)(0.61030.2360.121030.815)146kJ1 122n11.310.60.2361030.121030.815U CV(T2T1)0.7174()109.5kJ/kg0.2870.287PvPvQ1 1T1,22T2RRh CP(T2T1)153.3kJ/kgW S CPlnv2P0.8150.12Cvln2 0.1144ln0.7174ln 0.089kJ/(kggK)v1P0.2360.614-114-11Pv1 1 RT1 v1RT
6、10.287573.15 0.274m3/kg3P0.6101P1 0.6mPa,T 573.185Kv2 3v1 0.822m3/kg v 1T2T11 573.15()1.41 369.3K3v2RT0.287369.3P22128.95kPav20.8221v3 v1 0.274m3/kgT2T2 369.3KP3W RT30.287369.3 386.8kPav30.274P1R(T1T2)RT2ln21P31128.950.287(573.15369.3)1.287369.3ln 29.8kJ/kg1.41386.84-164-16n ln(P2/Pln(P2/Pln(0.5/0.1
7、)1)1)1.13TP0.5 289.15ln(v1/v2)ln(1g2)ln(g)0.1 248.15T2P111P2nnn1.134000.51.1361.13Pv)0.110 1()1178.7kW1 11(n1P11.131600.1Ws,nPv0.11064001 1Q m 482kgRT1287289.15H mCP(T2T1)4821.0044(348.15289.15)28563kJQ H WS 285631178.760 42159kJ/min第五章5-35-31-2 过程：定压吸热Q12 mCP(T2T1)1.011000300 707kJW12 RT2T1 0.28710
8、00300 200.9kJ2-3 过程：可逆绝热膨胀Q23 0,T3T1 300KW2311RT2T30.2871000300 502.25kJ11.413-1 过程：定温放热T3 p3T2p21 p31.478kPa p 1.478W31Q31 RT ln3 0.287300ln 362.817kJp1001净功W0 Q12Q31 344.18kJW0344.18 48.68%Q127075-11（1）由热力学第一定律得Q U W W 10030 70kJ（2）S Q1Q2100Q2 0.026 Q2115.6kJTT600600则气体放热 115.6kJ.回到初始状态U 30kJW Q2U 115.630 85.6kJ