摘要
由于制冷剂R11对臭氧层有巨大的破坏作用,要完成用R123对R11的替代工作,需要对其替代工质R123换热性能进行细致研究.对替代工质R123饱和蒸汽在5种水平单管外凝结换热的特性进行了实验研究,冷凝温度分别为38℃、40℃、42℃.实验结果表明,光管外的凝结换热系数实验值与Nusselt理论值符合较好,最大偏差不超过±10%.低肋管和锯齿管均能起到明显的强化换热作用,其强化倍率在8.4～16.0之间,且锯齿管的性能优于低肋管.通过实验研究还对R11和R123在强化管外凝结换热特性进行比较,证明选用R123来替代R11凝结换热方面有一定的可行性.
Experimental studies on the condensation heat transfer coefficients of R123 saturated vapor outside five single horizontal tubes were conducted. At the saturation temperature of 38℃, 40℃, and 42℃,experiments show that the results outside the smooth tube agree with those from Nusselt Equation with a maximum deviation of ±10%. Both the integral-fin tubes and the saw-tooth tubes present high heat coefficients, which are about 8.4～16.0 times of the smooth tubes, while the saw-tooth tubes behave more preferably. The comparison of R123 and R11 is also conducted in this study.
出处
《现代电力》
2005年第1期52-55,共4页
Modern Electric Power
基金
西安交通大学动力工程多相流国家重点实验室资助课题
关键词
制冷剂
替代工质
凝结换热
强化换热
水平单管
实验研究
refrigerant
alternative refrigerant
film condensation heat transfer
enhanced heat transfer
single horizontal tube
experimental study
