福州大学2002-2003学年第二学期
化学系化工原理期末试卷(A卷)
一、填空、分析题。
1、抛物线,2,2
2、调节出口阀的开度,旁路阀 3、V~H,V~N,V~?,转速,水
4、?1??2??3??4
5、增大,减小,增大,挥发度 6、壳,管程 二、计算题
解:(1)在1—1与2—2处列柏努利方程
22p1u1p2u2z1???z2???hf
?g2g?g2g?z1?z2?4m,p1?p2,u1?0
23u2w2 ? u=4.43m/s 4??2g2gQ??4d2u?0.785?0.12?4.43?3600
?125m3/h?0.03478m3/s
(2)在1—1与M—M处列柏努利方程
2p1u12pMuMz1???zM???hf,M
?g2g?g2g?z1?z2?3m,p1?0,u1?0,uM?u2?u
2pMu213u 3?????g2g22g2?pM5?4.43?3??2.5m ?g4?9.81pM?2.5?1000?9.81?2.45?104Pa
三、计算题
lu2解:hf???
d2g20u2?0.02???0.41u2
0.052?9.81He?20?1.12?105Q2
?20?1.12?105?(d2u)2
4?20?1.12?105?(0.785?0.052u)2 ?20?0.431u2
p11000?0.1?10??1.25m?液柱? ?g800p21000?0.5?10??6.25m?液柱? ?g800在1—1与2—2处列柏努利方程
22p1u1p2u2z1???H?z2???hf
?g2g?g2g??z1?0,z2?8m,u1?u2
1.25?(20?0.431u2)?8?6.25?0.41u2
?u?2.89m/s
V?0.785?0.052?2.89?5.66?10?3m3/s
He?20?1.12?105?(5.66?10?3)2?16.4m Ne?HQ?g?16.4?5.66?10?3?800?9.81?728W
四、计算题
解:(1)u?Q5000/(3600?770)???0.919m/s
0.785?d20.785?0.052du?0.05?0.919?77044Re???8.23?10?10 ?3?0.43?10?0.80.4??0.023?RePr
d?0.023?0.207?(8.23?104)0.8?5.480.4?1361W/(㎡·℃) 0.05(2)ms1cP1(t2?t1)?ms2cP2(T1?T2)
?ms1?ms2cP2(T1?T2)5000?2.64?(65?35)??3783kg/h
cP1(t2?t1)4.187?(45?20)(3)?tm??t1??t220?15??17.4℃ ?t120lnln15?t2Q5000?2.64?103?(65?35)/3600A???14.7m
K?tm430?17.4ld??A?l?五、计算题
A14.7??82m ?d3.14?0.057?F?W?D解:(1)?
F?x?W?x?D?xfWD??200?W?D?D?94kmol/h ????200?0.5?0.1W?0.95D?W?105kmol/h??D?xD94.1?0.95?100%??100%?89.4% F?xf200?0.5(2)y???x2x?
1?(??1)x1?x?饱和蒸汽进料,??0,ye?xf?0.5 ?0.5?2?xe ?xe?0.33 1?xeRmin?xD?yfyf?xe?0.95?0.5?2.65
0.5?0.33R?2?Rmin?2?2.65?5.3
V?l?D?(R?1)D?(5.3?1)?94?592.2kmol/h
V'?V?F?592.2?200?392.2kmol/h
(3)?y1?xD?0.95
?y1?2?x1?0.95 ?x1?0.905 1?x1?y2?y2?xR5.30.95x1?D??0.905??0.912 R?1R?16.36.32?x2?0.912 ?x2?0.828 1?x2