程煤油的定性温度为9T=240140?=90(℃)管程流体的定性温度为t=24030?=35(℃)根据定性温度,分别查取壳程和管程流体的有关物性数据。煤油在90℃下的有关物性数据如下:密度30/825mkg??定压比热容℃??kgkJcp/(22.20)导热系数0?=0.140W/(cm??)黏度sPa??000715.00?循环冷却水在35℃下的物性数据:密度3/994mkgi??定压比热容℃kgkJcpi??/(08.4)导热系数)℃mWi??/(626.0?黏度sPai??000725.0?3.3计算总传热系数3.3.1热流量0m=243001000000?=138888.9(kg/h)6108333358.30)40140(2.29.138888?????kWh816.8564/kJ?3.3.2平均传热温差℃tttttm39304040140ln)3040()40140(ln2121'??????????????103.3.3冷却水用量hkgtcQwipioi/755719)3040(08.4108333358.306???????总传热系数K管程传热系数??℃mWi?????????24.038.0/6931)626.0000725.01008.4(4387302.0626.0023.0?壳程传热系数.假设壳程传热系数600?o?w/(m2℃,污垢热阻?SiR0.000344℃/w,0Rs=0.000172m2℃/w,管壁的导热系数)/(45cmw????则总传热系数为:osomoiosiiioRdbdddRddK???11?????6001000172.00225.045025.00025.0020.0025.0000344.0020.06931025.01???????????℃m??2/3.39843873000725.09946.1020.0Re????i
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