冷藏集装箱小管径冷凝传热关联式适用性研究

Suitability of condensation heat transfer correlations for small diameter tube in refrigerated container

研究了制冷剂R404A在冷藏集装箱冷凝器外径为5 mm的内螺纹管中的传热性能,设计了实验装置来验证已经提出的众多并不直接适配的传热关联式,大量对比由关联式计算与实验测得的数值的偏差,研究关联式的适用性及可修正性。研究表明Dobson and Chato冷凝换热关联式加以修正能很好预测R404A在内螺纹管中的冷凝传热系数,与实验值正偏差为+15.51%,负偏差为-14.13%,可为换热器设计计算提供较准确的理论指导。

Condensation heat transfer performance of R404 A for 5mm outside diameter horizontal microfin tubes in the condenser of refrigerated container was studied.Experimental device wasdesigned to verify heat transfer correlations which have already been proposed but did not meet the conditionsdirectly.In order to demonstrate the applicability and revisabilityof the correlations,deviation between the calculated and experimentally measured values was comparedthrough a large amount of data.The research results indicated that modified Dobson and Chato condensation heat transfercorrelation showed good predictability of condensation heat transfer coefficient of R404 A in small diameter microfin tubewithina deviation of-14.13% to 15.51%.The correlation could provide more accurate theoretical guidance for the calculation and design of heat exchanger.