第六章传热一、填空1、不变,减小2、<,=,=3、λ24、增加了壁面处的温度梯度,增加了壁面处的热流密度5、0,1,-1/4,3/4,2.5,3.56、20.8,21.8,20.87、水蒸气8、滴,膜,膜,核,膜,核9、30℃10、↓,↑,↑,↑11、↓,↑,↓,↓12、<,<二、作图题1、2、3、三、找错1、(C)(D)2、(D)四、计算题1、(1)(2)(3)22Tt21221ttTTCt100212tTCT502Ct125212TtCt2002CT12522、44521061810.21001.202.0269785.03600/800044RednqdndqdGdumm7.0707.01087.21001.21001.1Pr253PcCmWdair24.08.0/338.98PrRe023.0CmWKair2/338.98CtTtTtTtTtm703.41ln)()(2121WttcqQpm5122210244.2)(272.54mAtKAQm需268.50269302.014.3mdlnA实际需实际AA不适用3、原工况:新工况:不变;改变WttcqQpm5122210672.1)(Ctm28.43CmWtAQKm2/53.15431047.4111油水KCmW2/65.223水111,,mqTt2,mqn794.0)'()'()'('8.08.0228.0nnqquumm水水CmW2/58.177'水310631.71'1'1油水KCmWK2/04.131'220258.0''mAnnA)1(ln2211111221pmpmpmcqcqcqKAtTtT)'1(''''ln2211111221pmpmpmcqcqcqAKtTtT261.0''ln1221tTtT5.16.06.0'''1221112211221221ttTTcqcqcqcqttTTpmpmpmpm以上两式联列:以上两式联列:,Ct26.45'2CT11.62'24、441010229.14RednqdGdum7.0729.0PrPcCmWdKOH24.08.0/35.68PrRe023.02213.27mdlnAA换热器:逆流、操作线斜率为1'1tTtm)'()'(1122tTKAttcqpmCt29.121'CTA71.58B换热器:并流)5.01(5.0'ln22111121pmpmpmBcqcqcqKAtTtT574'21tTtTB15.0'112211pmpmAcqcqttTT15.0'112221pmpmBcqcqttTT以上两式联列:Ct62.1352CTB67.135)()(1111222TTcqttcqpmpmCT19.97