9-11
（1）pc??p0?0.528?1?0.528 MPa
Tc?T0??800?0.528?666.57 K
RT287?666.57vc?c??0.362m3kg 6pc0.528?10??1?1.41.4?1cc?44.72T0?Tc?44.72?800?666.57?517m/s
c（2）由M?得
a2cp?T0?T2?2000??800?T2???2?T2?443.56 K
?RT21.4?287?T2?T??443.56?p2?p0?2??1???0.127 MPa ??800??T0?RT287?443.56v2?2??1.002m3kg 6p20.127?10???11.41.4?1c2?44.72T0?T2?44.72?800?443.56?844.32m/s
fcfc??cc?22 ∵mvcv2fcccv220?10?4?517?1.002f2???3.99?10?3 m2
vcc20.362?844.32fccc20?10?4?517??（3）m??2.86 kg/s
vc0.3629-12
pc??p1?0.546?2?1.1 MPa p2?pB?0.1 MPa
cc?2?h1?hc??2?3024?2886??103?525.4 m/s c2?2?h1?h2??2?3024?2464??103?1058 m/s
fmincc20?10?4?525.4??m??5.25 kg/s
vc0.20f2?工程热力学
?25.25?1.55mv??0.0077 m2 c2105846
9-13
pc??p1??0.546?1.6?0.874 MPa ?pb ∴p2?pb，应采用渐缩喷管
c2?2?h1??h2??2?3228?3148??103?400 m/s
f2c22?10?4?400??m??0.333 kg/s
v20.249-14
查h-s图得：x1?0.97，t1?213℃
21?j????43.7 K/MPa ????p?hp2?p10.1?2.0??T?T?T130?2139-15
c2?2?h1?h2??2?3220?3170??103?548 m/s
c2???c2?0.93?548?510 m/s
22c2c25482?5102????10?3?20.1 kJ/kg 2229-16
?s?cvlnT2v?Rln2?0.287ln2?0.199 kJ/kg?K T1v1?exh?exh1?exh2?h1?h2?T0?s2?s1? ?T0?s?300?0.199?59.7 kJ/kg19-17 （1）∵h1?c12?h2
2
??1??2?RT1??p2??c1?2cp?T2?T1???1??????1??p1?????0.4?2?1.4?287?300?1.4 ??2?1??363.3 m/s1.4?1??
（2）M?c1c1363.3???1.05?1 a?RT11.4?287?300应选择渐缩渐扩扩压管。
工程热力学
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