工程热力学-课后习题答案--可打印-第三版-第二章

62-1134.144000kJ/kg30.75g/cm64kW33334.110m750kg/m44000kJ/kg1125300kJQ−=×××=3600(1125300643600)kJ/h894900kJ/houtQQW=−×=−×=2-21kg2-130.5MPa272l10kg212ln0.26kJ/(kgK)(273.1527)Kln54.09kJ/kggVAhwRTVAh×==⋅×+××=2200212''()22mmWWcpVVc=+∆=−+a3111611kg260J/(kgK)300.15K0.1561m0.510PagmRTVp×⋅×===×32120.3122mVV==(a)36322(54.09J/kg1kg100.110Pa0.1561m)/10kg87.7m/sc=×××−××=2-350J84JJQUW=∆+50J84J34JWQU=−∆=−=−34J2-46310kJ×375kW50100W0mElessQQQQQ=+++=6375kJ/s3600s1.3510kJmQ=×=×500.1kJ/s3600s18000kJEQ=××=666310kJ310kJ1.3510kJ18000kJ1632000kJlesslessmEQQQQQ=−×=−−−=×−×−=72-5280.1MPa0.06kW0.1kW418.7kJ1800kJ/h215m3.0m0.72kJ/kguT∆=∆62g0.110Pa15m3.0m52.06kg287J/(kgK)(28273.15)KpVmRT×××===⋅×+QUW=∆+W=0QU=∆(0.10.06)kJ/s3600418.7kJ31800kJ0.86K0.720.7252.06kgQsTm+×+×−∆===×2-62-1430.28m30.99m61m/s2722kgQUW=∆+0=Q20212()2mWpVVc=−[phone]kg()0.110Pa(0.990.28)m(61m/s)22mUpVVc∆=−−−=−××−−×3499.310J499kJ=−×=−2-72-1530.008m170.1013MPa0.1MPabp=20.08m40000N/mK={}{}kJ/kgK0.718uT∆=∆0.15MPa1bmgpApA×+×=×6212()(0.10130.1)10Pa0.08m10.61kg9.80665m/sbppAmg−×−××===863311g10.101310Pa0.008m9.7310kg287J/(kgK)290.15KapVmRT−××===×⋅×3120.008m0.1m0.08mVhA===20.3MPap=2622232632223g321()(0.150.1)10Pa0.08m10.61kg9.81m/s0.0974m40000N/m()0.08m(0.10.0974)m0.0158m0.1510Pa0.0158m848.26K9.7310kg287J/(kgK)()9.7310kbaVppAmgxKxVAhxpVTmRUmcTT−−−×−×=−××−×===+=×+=××===××⋅∆=−=×g0.718kJ/(kgK)(848.26290.15)K3.90kJ×⋅×−=2221d()dbAWpVpAmgKxAV==+×+∫∫212221216222()d()()()240000N/m(0.110Pa0.08m10.61kg9.81m/s)0.0974m(0.0974m)2979J0.98kJbbpVmgKxxKpAmgxxxx=+×+=+−+−=××+××+×==∫3.90kJ0.98kJ4.88kJQUW=∆+=+=2-80.1MPa30.3m0.15MPa1217g287J/(kgK)R=⋅{}{}kJ/kgK0.72uT=0()pppkVb∆=−=+a310.3mV=0p∆=320.6mV=0.05MPap∆=ab=–0.05k=0.1660.16670.05pV∆=−96311g10.110Pa0.3m0.360kg287J/(kgK)290.15KpVmRT××===⋅×(1)22112601d()d(0.16670.050.1)10d37500J37.5kJvvvvWpvppVVV==∆+=−+×==∫∫∫(2)63021()0.110Pa(0.60.3)m30000J30kJWpVV=−=××−==37.5kJ30kJ7.5=−=−=(3)63222g0.1510Pa0.6m871.08K0.360kg287J/(kgK)pVTmR××===×⋅21()0.360kg0.72J/(kgK)(871.08290.15)K37.5kJ188.1kJQUWmuuW=∆+=−+=×⋅×−+=2-910.1MPap=310.845mkgv=20.1MPap=320175mkgv=kg146.5kJ50kJ10kg1kg21kg31quw=∆+50kJ/kgq=−146.5kJ/kgu∆=50kJ146.5kJ196.5kJ/kgwqu=−∆=−−=−196.5kJ(2)1kgtwtqhw=∆+2211()()twqhqupvqupvpv=−∆=−∆−∆=−∆−−333350kJ/kg146.5kJ/kg(0.810kPa0.175m/kg0.110kPa0.845m/kg)252kJ/kg=−−−××−××=1252kJ310kg1/6kg/s1qkg/s252kJ/kg42kW6mtNw==×=102-1040T/h9MPa3441kJ/kg0.0974MPa2248kJ/kg56.8110kJ/h×1101325Pa2370m/s140m/s41.6m11,19MPa0.101325MPa9.1MPaebppp=+=+=22,20.101325MPa0.0974MPa0.392510MPabvppp−=−=−=×2tQHW=∆+576.8110kJ/h401000kg/h(34412248)kJ/kg4.70410kJ/htmPHqhψψ=−∆=−∆=−×−××−=×&74.70410kJ/h13066.7kW36003600tWP×===3222121222132223()'()2'()()2401013066.7kJ/s(14070)(m/s)102360013066.7kJ/s81.7kJ/s12985kWmmiffmimffqqhhPccqPqhccψψ−=−++−=−∆−−×=−×−××=−=81.7kW42()40000kg/h13066.7kJ/s9.81m/s(1.4)m3600s13066.7kJ/s0.174kJ/s13066.9kWimmPqhqgzψ=−∆−∆=−××−=+=0.174kW2-116m30m325m/h12kW3.54?(4.187kJ/(kgK)pc=⋅phct∆≅∆31000kg/m)11222121()()2ffsmQHccmgzzW=∆+−+−+21()sQHmgEEW=∆+−+2121[()()]psmcttgzzW=−+−[phone]kg/h[4.187kJ/(kgK)(43.5)C9.81m/s(306)m10]12kJ/s3600s1.810kJ−=××⋅×−+×+×−×=×o31.810kJ/h×2-1230.028mV=0.1MPa210.7MPa21Cpt==°0.2MPa{}{}kJ/kgK0.72uT={}{}kJ/kgK1.005hT=22CV2222111111δd()δ()δδ22fffiQEhcgzmhcgzmW=+++−+++δ0Q=δ0iW=2δ0m=122fc21()gzz−CV11dδdininEhmhm==inCVminEh∆=CVEU∆=∆in21mmm=−221121()inmumuhmm−=−21112111222()()pininVVVcTmmmcThmmmuTmcmc−+−+==a63111g10.210Pa0.028m0.0332kg287J/(kgK)294.15KpVmRT××===⋅×6222g2220.2100.02819.5287pVmRTTT××===×bab20.0571kgm=2342.9KT=2-1314MPa1730.008m0.15MPa12{}{}{}{}kJ/kgKkJ/kgK0.6570.917uThT==gpVmRT=kg22CVδd()δ()δδ22ffoutiniccQEhgzmhgzmW=+++−+++δ0Q=δ0outm=ddCVEU=2,2finincgzdδδ0ininiUhmW−+=0δdiWpV=222021()0inmuhmpVV−+−=2202()0inmuhpV−+=a222g2pVmRT=(b)322g0.15MPa0.008m260J/(kgK)pVR===⋅{}{}22kJ/kgK0.657uT={}{}kJ/kgK0.917ininhT=ab2313.20KT=20.0147kgm=2-142kg180kJ2kg3600J301.7kJ/kgh=20kg270.72kJ/(kg.K)VVucTc==22foutoutoutuoutucQUmhmUmhWUQmhW=∆++=∆++∆=−−180kJQ=out2kgm=301.7kJ/kgh=3.6kJuW=180kJ2kg301.7kJ/kg3.6kJ427kJU∆=−×−=−13212211()VUUUcmTmT∆=−=−21TT=211()2kg0.72kJ/(kgK)300.15K432.2kJVUmmcT∆=−=−×⋅×=−21TT=