热工基础与应用课后习题答案(全)第二版

7.用UUU习题p5bpppgbpppbgppp755700bvppp0vb图，p＝ghsin980Pa3ppp756b水柱ppp1bappp21bpppCb2ppH真空室b汞柱ppp2360362kPa1真空室appp362170192kPa21bppp1922190kPacb真空室1Fpπ24bppp＋pb水柱汞柱WVpdVV)10200KJ6212V1pVpV1110.3WpdV0.50.3dVV)111.3V210pcDcpp150000c5000001DD1111WVDD(D)c3DDD)43412226282VD11118)44W0.30.04)10dV1.7610J640.1W摩擦力JWW6J4活塞摩擦力WpV102110J65解：确定为了将气球充到2m3p）bp2)p2)0.910(22)5p11.810Pa52121VV2113Wp0.91021.810J55bpV贮气罐贮气罐2V＝气球＋贮气罐3pbV33气球3WJ55⑵⑶⑴⑵⑶⑷nk⑸nk⑹nk4.5.W与W；U与U；(3)Q与Q图46.quw⑴⑵⑶⑷ququvpv)2211qupv)217.习题解：WQ30kJWQWQ200065012001450kJ膨吸压放Q21036007.210J/h36baUUQW1004060kJabbaQW602080kJadbabbaQUUWW603090kJbaabababUUU604020kJadbdQUUU20kJdbdbdba-d过程系统与外QUUWUW40(20)60kJaddaadadadbU500q2257kJ2122571.0110(0.0011.674)2088kJ2Gpp110551Ab4G4pp210552AbTTT120pV2.93910100101010254V10m3311p1.95910522VV3621A4QWpAΔL1.9591010010542wqwq50146.5(0.80.1750.10.845)10252kJ3swsP42kWq100)10kJ5热源53Q310101.0210kJ555p1VV()p11(10311212pV1.211V)0W1.781.78pV1.22111V1.211QWQhqhqhqW6m67m71m1sqqqm6m7m1Qqh)qh)Wm161m767sPWQhh6s67m71031m131QHmcW22fShupv210010102329400J361111hupv150010101656000J36222211WQHmcm(qhc)2f2f22s14[2329400)2322PWscccc和和pvpvcccc和和pvpvc|c|c|t、t、t122tt2100t1c|c|c|2t、t、t1200t1tcdt1ct)0t01t110tcdt2c2)0t0t220tcdt2c2)ttt1tt212t11c|c|t>t21t01ctcttt21c221cc0cc2221220tttttt0tt21ttt0t11011021c|t2t1tcdtttcdtt)2tcdtt1tcdtt112211cct2t0t00211tt12tt1200t)tct)tctc)tttt122112121121100tt011tt12tt12c|t10RTgdquw)dudwdudvducpRdTdTdTdTdTdTdTg4.uv在12u34v1v线TccduPdvP1dvcdvucvcPPvR112c和c为常数，且考虑到v0122ucv1uqw0qw0气体对外做功，体积增加，cc1u1c21vk1vkk1c、c215.pvTs图⑴⑵nnqwu、、⑶⑷qwu、、pTn=0n=0An=1n=1A1<n<k1<n<kn=±∞n=kn=±∞n=kvsRqcTTT2n1V211R所以：c1nkn1Vp－vAApTn=0n=0An=1n=1A1<n<k1<n<kn=kn=kvsRqcTTT2n1V211R所以：c1nkn1Vn=1.6n=1.6n=kTpn=0n=1n=0n=1n=1n=kAAn=±∞n=1.6n=kvsnpvA向TsApTn=0n=0An=1n=1An=1.3n=1.3n=kn=kvsnpvA向TsATs在TsTsTwiMxiiwiMiccpvuxumimiixuiiccpvCC(xCxC)xRRiiimmiiT0图图Ma1Ma1习题p、T和S222p、T和S222pp；TT2221STpTSSSmclnmRlnMcln221TpT22pgp222STT)21ppTpT1kk1kk1221TkSMS]p)p)Skpp()p11kT211112pgp、V、T和m解：设气体的初态参数为，阀门开启时气体的参数为1111p、V、T和mp、V22223333VVVmm。12312105p8.757TT2932Kp211pV7100.0275mm11RT28729312g1105pVpV105m3333RTRT2873g3g2mm0.2250.21623p、V、T和mp、V、T1111111p、V、T和mp、V、T2222222mRT287303V1g13p10611mRT0287303V2g23p10622VVVV3总1212ppp1pVpVpV11TTT2pVpV－V）,11122TT22总T1111222p10Pa5T600K2V1pp6.0102.010Pa515V3212dTp12c52Tp3pg11pTT()()1k1kp氢2氢2pVT1005V＝＝3氢氢21pT10288氢25氢2V3pVT1.9614102885T空2K空2空2pV0.9807100.151QUUU＝mc－T)mRT)g氢氢2k1空氢空空2氢pVRTpV＝c－T)空2RT)RTg氢氢2g空100g氢5＝＋2872881001541572881G1959.8pp11.0281052.93910Pa15A10010b4G959.8100104pp21.0281051.95910Pa25AbpVV()100101010()1.3410m111/k4233p212p1.959k1TT()300()2kp2.939211VV3321A4TT303K12mRT6287303VVg13p1mRT0.310616287303g2p310622VWVpdVmRTln6287303ln22Vg1V11QW⑵kpk1WVpdVpV()]22kk1p11V111.4111610303()]33Q0p0.1k11.41TT()303()2k1.4p0.3211⑶p0.1n12nTT()303()p0.3211mRTp62873031n11W()]()]g12nn1p131QmcT)nk6n11V21p1k11TT()293()1kp212pV147.1100.04325m11RT83142931g1pV73.55100.04325m2RT83142g2mmm12T293K3T293pp10310Pa55T322pV10325m22RT83142932g2R2wT)kJgn1nkn1122qRcT)kJV21cgk1Vk1kn5)TVTVn1n111.494n11121)2212k把nw(n103RTT2240g12Rk11cRccVgPgVpVT10132550010473V8773m311Tp201062121Dc3600VD242t1300)t11P0t400)t22P0ctcttt400130090021cP)tP2P1002ttt121dTpTps2cRcR222TpTpPgPg11118ABA和BpV106mAART287300AgApV106mBBRT287300BgBm＝m＋m总ABTp1pcD，VD63Bp106DcN53mRT总g11mRTcD(DV)mRTDVD4366c总gA总gA3Bp551VD336R8314RcM29gu700103T620VcRcVPghcTPscRTvT2v2Vg11p、T、Vp、T、V。111222⑴v1TT()()11k1v2212WnCT)1000V12s0⑵TT340K21h0TvTvSlnRln)lnc]2222Tv1Tv1VVV11100055cR)2727vcR)P22T480k1.4p()p()0.12k10.4T300211c0.717180Vw129kJtCu11tCu22uuu21wupmTm106154m3标标1Tp体2标1pmT标标2Tpm3标2pm101325108000287273m＝＝标体，标RT质g标Qm（hh）1质2c)20P0c)270P02702027020cP)27020Qmh）质2177cR)22PQm（hh）质21m0.14500.056co12mm5075co212mm0.06500.232755075o1o222mmo212m0.0550HO10.022mm50752HO21ωN211MiMiR8314R)M28.85gMM0.12440.05320.79280.041829.72iiRR8314R)MM29.72iigpm标T1013253010105533m标6.2810m532体，标Tp标2730.98105255R)TgRMRg1MiMi1iN22RM：g26R5RgMRg2535,O221ωM⑵M28iMi32823xN23228ppxNN22CdTRlnvV2ss22Tv1g11TvssClnRln22Tv121Vg1n1CVg11nnRvPTPn;g2121vPTPk1V12121n1RPPnkpnnsslnRlnRln2g12k1PPp21gg211n1CVg1RvTn1g21vTk1V121Rk)RTTTn1sslnRlnln2gg21k1TTT21g121T为p和p12Rlnp2pg1在TV和V时12Rlnv2vg1RT298v1g1p10513RT473v2g2p10523由c和cPVckPcVccRcc)PVgPVucT)175V2T1p4734sclnRlnlnln)22Tp298Pg11HQmcT)Qp21QQ3349103m(TT)10)3ccR74129721pVgUmcT)107413V21QR33490.297WmR(TT)958KJgCR0.7410.297g21vg10pV11R6nTnT11pV22R106nTnT22HcnTccRVPcMVcVUncTVccP)M⑴nRTVW2PdV2dVnRTln8314373gV2Vg111VSRln83142Vg1⑵VSRln83142Vg1⑶VSRln83142Vg1P，crk22PPcrk11k111111PRTP2871023kkvv1113PPP010216212Pv22R6T2ccTT22P1qv0m2A2c22k122PPcrk110515k11122k2pk2p2qA2mmink1A2mink111k1k1k1k1v11212524111c12ccTTTT1acaP1aaPkT6731kPP10611aT1a12kPp()0.528MPak1k1cr12k2P2102212qA2()2510k11k1k1v42287673maxmin11k11PPRT287kv2v13111P2PP10621qvmax2c2m/sA251024c21202TT6052.8C*21004Pk1k11P1TT3532P121ccTT22P1c252239/s'2222c22TT35322c221PRT287v223P1062cA16104q22vm2c21002TTTTTT2932932932cPc2220022cPc2240022c2PkTk1PPPPPP1061061061T293kT293k11TkT293k11T1.2.3.和4.⑴⑵⑶；⑷；⑸⑹5.6.7.8.9.5习题由,Q2又即000的dT=s习题，查h-s时kJ/kg)kJ/kg.K),P2,,,时，当时当，时，，MPa、d，h，沿定d沿定d由及由,CT-s图。p-v图与用C=4MPaC11112=s=4KPa2122P=P=4KPa323=h113=h12==P=4MPaC11112s=s=4kPa2122P=4kPa,33=h113=h12==1点：由P=13MPaC11h115s=s51P552，P=7KPa2h22P=P32h31点：由P=6MPa,tC11hs112s=s,P=6kPa212h2P=P32h3：q=h113w=h121点：由P=10MPaC11h11a点：由s=2MPaa1aha2点：由s=s,P2a2h2P=P32h3P=P5ah5w)s15到22到33到5解:(1)每kg到22到33到41到22到35到13到4由1到2由2到3由3到4由1到2由2到3由3到4由1到2由2到3由3到4p-vpvhhhhhh211415h=1670kJ/kgP11h=1789kJ/kgP22h=h=489kJ/kg43q=hh=1181kJ/kg214h=h=536kJ/kg34h=1532kJ/kgh=1703kJ/kg12h=1670kJ/kgh=1820kJ/kg12h=h=512kJ/kg34由m=hkJ/kgh540kJ/kg12hhkJ/kg34Ch=500kJ/kgh=525kJ/kg12h=225kJ/kg4C：h=550kJ/kg2h=h=240kJ/kg34C。习题m为·K)22·K)和22与8-5.有一厚度为空气温度为℃，和墙内壁面之间对流换热的表面传热系数为·22由2和10W/(mK)和W/(mK)。冷库C和30C2K)和322W/(mK)和W/(mK)，炉墙内外壁面温度分别维持700C和80C由过2C和C图CC、C、。3C、C、C及C即CCW和K)；第二CC由<9-8题中的C、、、K)、C、C、2K)，CC52解:，K)、解：解:，3CC2由由C、直径为CC3解:由由5CC2K)、热扩散率m2C由由CCK)。23K)。C即即由2CC2C5C2m10-1水和空气都以速度m/s为50C，试求距平板前沿100mm处流动边界层及热边界层的厚度。解：对水：由查附录3水的物性表得到：，，对空气：由查附录2空气的物性表得到：，，10-2试求水平行流过长度为0.4m的平板时沿程m处的局部表面传热系数。己知水的来流温度为20C，速度为的壁面温度解：由C。查附录3水的物性表得到：，，当x=0.4时，为旺盛湍流，不应再用那个公式。当时，时，时，时，当当当10-3均表面传热系数以及单位宽度平板的换热量，并对比这两种情况的计算结果。解：由查附录2空气的物性表得到：，，当时，平均表面换热系数为单位平板宽度的换热量为：10-4如果用特征长度为原型1／5的模型来模拟原型中速度为6为200C的空气强迫对流换热，模型中空气的温度为20C。试问模型中空气的速度应为多少？如果测得模型中对流换热的平均表面传热系数为200W/(m2K)，求原型中的平均表面传热系数值。解：由附录2得到：当空气温度为20C时，0，当空气温度为200C时，0，(1)由相似原理：，所以有(2)由相似原理：，所以有10-5水在换热器管内被加热，管内径为14mm，管长为2.5保持为110C，水的进口温度为50C，流速为1.3试求水通过换热器后的温度。解：假定出口温度为70C，则有：0，查附录水的物性表有:,,,,,采用紊流换热关系式：所以，校核：重新假定出口温度为100C，则有：0，查附录水的物性表有:,,,,,采用紊流换热关系式：所以，校核：可见Q和Q相差很小，所以2110-6用内径为0.0162.5m的不锈钢管进行管内对流换热实验，实验时直接对不锈钢管通以直流电加热，电压为5V，电流为900A，水的进口温度为20C，流速为0.5换热的表面传热系数及换热温差。解：假定出口温度为40C，则有：0，查附录水的物性表有:,,,,,采用紊流换热关系式：所以，校核：可见Q和Q相差很小，所以2110-7空气以1.322mm2.25m平均温度为38.5C，管壁温度为58C，试求管内对流换热的表面传热系数。解：查附录空气的物性表有:,,,,，,为层流，采用常壁温层流换热关系式：所以，10-8如果上题中空气的流速增加到3.