第三章纯流体热力学性质的计算选择合适的普遍化关联方法计算1kmol丁二烯-1,3从2.53MPa、127压缩到3-1512.67MPa、227℃C时的AH、△S、△V。已知丁二烯-1,3的T。=425.0K、P。=4.32MPa、V。=0.221m3.kmol-、Q=0.181,理想气体等压热容Cp = 22.738+222.796×10-3 T-73.879×10°T2 (kJ-kmol-l.K-l)或Cp=2.735 +26.7977×10-3T-8.8861×10-6T2(K)/R_ 400P= 2.53=0.941、P,I == 0.585解:初态:T425PcT.4.326T2500P 12.67 =2.928终态:Tz=P,=1.176、T425Pe4.326初态用第二维里系数关联式较合适,终态用普遍化压缩因子关联式较合适。真实状态1真实状态2400K2.53MPa500K12.67MPa理想状态理想状态理想状态500K12.56MPa400K2.53MPa500K2.53MPa(a)使用普遍化第二维里系数计算△H,△S,0.4220.172B°=0.083-B'= 0.139 --0.383-0.084T, 16T,4.2BPz, =1+=0.752RTV=ZRT_0.7528314x10 400=0.98m -kmollP2.53×106dBo0.675dB_0.722=0.793= 0.9967,2.6dT,"T.,s?dT,I1
第三章纯流体热力学性质的计算 3-15 选择合适的普遍化关联方法计算 1kmol 丁二烯-1,3 从 、 压缩到 、 时的 53.2 MPa C 0 127 67.12 MPa C 0 227 H 、 S 、 V 。已知丁二烯-1,3 的 、 、V 、 TC 425 0. K PC 32.4 MPa 3 1 0 221. m kmol c 181.0 ,理想气体等压热容 * 3 26 11 10879.7310796.222738.22 CP T KkmolkJT 或 T KT R CP 3 26 * 108861.8107977.26735.2 解:初态: 941.0 425 1 400 1 C r T T T 、 585.0 326.4 1 53.2 1 C r P P P 终态: 176.1 425 2 500 2 C r T T T 、 928.2 326.4 2 67.12 2 C r P P P 初态用第二维里系数关联式较合适,终态用普遍化压缩因子关联式较合适。 (a) 使用普遍化第二维里系数计算 11 SH 383.0 422.0 083.0 6.1 1 0 Tr B 084.0 172.0 139.0 2.4 1 Tr B 11 752.0 1 0 1 1 r r T P BB RT BP Z 3 1 6 3 1 11 1 988.0 1053.2 40010314.8752.0 kmolm P RTZ V 793.0 675.0 6.2 1 1 0 r Tr dT dB 996.0 722.0 2.5 1 1 r Tr dT Bd 1
HRdBodBROB'DRT.dTd=0.585[-0.383-0.941x0.793+0.181(-0.084-0.941×0.996)=-0.769H,R =-2716kJ.kmol-1SR( dBodB'-0.585(0.793 +0.181×0.996)=-0.569k)+0RdT,dT,JS.R = -4.734kJkmol-l.K-l"c'pdTTC(b)求理想气体从PT→P,T:T, - T,C"PmhA+BT.+4TR3已知:A=2.735,B=26.7977×10-5,C=-8.8861×10-6_T,+T,400+500=450K、Tm=-T_500-400448KTIn50022In400T,= 2.735± 26.7977 ×10- 450 ~ 8.8861×10*C"Pnth(4×4502-400×500)R3=12.987C'Pmh =107.972kJ-kmol-lC'pm = A+BTm +T TmR=2.735+26.7977×10-3×448+(-8.8861×10-×450×448)=12.949C*Pms =107.657kJ-kmol-!AH2=C Pmh(T,-T)=107.972(500-400)=10797.2kJ-RIn=107.6571n 500T2-8.3141n 12.67AS*2 =C*Pms In-=10.629kJ4002.53PT(c) 求AH,"AS,R由T,2 =1.176、Pr2=2.928查图2-14~2-20得:2
769.0996.0941.0084.0181.0793.0941.0383.0585.0 1 1 1 0 0 1 1 r r r r r C R dT Bd TB dT dB TBP RT H 1 1 2716 H kmolkJ R kJ dT Bd dT dB P R S r r r R 569.0996.0181.0793.0585.0 1 1 0 1 1 11 1 734.4 S KkmolkJ R (b) 求理想气体从 22 : 11 TPTP 12 * * 2 1 TT dTC C T T P Pmh 21 2 * 4 3 TTT C BTA R C am am Pmh 已知: 5 6 108861.8,107977.26,735.2 BA C Tam 450K 2 2 21 TT 500400 、 K T T TT Tlm 448 400 500 ln 400500 ln 1 2 12 987.12 5004004504 3 108861.8 450107977.26735.2 2 6 3 * R C Pmh * 1 972.107 C Pmh kmolkJ 949.12448450108861.8448107977.26735.2 3 6 * lmamlm Pms TTBTA R C * 1 657.107 C Pms kmolkJ Pmh TTCH 400500972.107 2.10797 kJ 12 * 2 * kJ P P R T T CS Pms 629.10 53.2 67.12 ln314.8 400 500 ln657.107lnln 1 2 1 * 2 2 * (c) 求 RR H S 22 由 176.1 、 Tr 2 928.2 Pr 2 查图 2-14~2-20 得: 2
(g: /r,-0(. -00、(.) =-1.15/RT(n.) -063k)、(s. / -175、 (s(s,R) = -14.55kj(6s)/ --12、 (5g -98H, -(H,") +o(H,") =-10600+0.181x(-4063)=-1135J mo-S,R = (s,")° +o(s,") = -14.55+0.181x(-9.98)= -12.74J mol-AS=AS, + S,R+S R=10.629+(-12.74)+4.734=2.623kJAH = AH, +H,R +H,R=10797.2-11335+2716=2178kJ.kmol-Z'=0.8查图2-6~2-9得:Z°=0.52ZRTV==0.2181Z =0.52+0.181×0.8=0.6648P△V=0.2181-0.988=-0.769m3
0.3 0 2 C R RT H 、 H kJ R 10600 0 2 、 15.1 2 C R RT H 、 H kJ R 2 4063 、 75.1 0 2 R S R 、 S kJ R 55.14 0 2 2 2.1 R S R 、 S kJ R 2 98.9 1 2 0 2 2 181.010600 4063 11335 HH H molJ R R R 1 2 0 2 2 74.1298.9181.055.14 SSS molJ R R R SSSS kJ RR 623.2734.474.12629.10 122 1 22 1 113352.10797 2716 2178 HHHH kmolkJ R R 查图 2-6~2-9 得: 52.0 0 Z Z 8.0 Z 6648.08.0181.052.0 2 2181.0 P ZRT V 3 V 769.0988.02181.0 m 3