水平内螺纹铜管内R404A的冷凝压降特性  

Condensation Pressure Drop Characteristics for R404A in Horizontal Micro-fin Tube

作　　者：何宽 柳建华[1] 余肖霄 王皓宇 HE Kuan;LIU Jian-hua;YU Xiao-xiao;WANG Hao-Yu(Key Laboratory of Multiphase Flow and Heat Transfer in Shanghai Power Engineering,University of Shanghai for Science and Technology,Shanghai,China,Post Code:200093)

机构地区：[1]上海理工大学上海市动力工程多相流动与传热重点实验室,上海200093

出　　处：《热能动力工程》2020年第1期140-145,共6页Journal of Engineering for Thermal Energy and Power

基　　金：上海市部分院校能力建设专项计划(16060502600)。

摘　　要：对R404A在内螺纹铜管内冷凝压降进行了实验研究。为了给R404A在小管径换热器中应用的可行性提供依据,研究缩小管径带来压降上升的特性,设置了不同的影响因素来研究R404A在内螺纹铜管中的冷凝压降特性。实验工况为:饱和温度35~45℃,质流密度200~900 kg/(m^2·s),热流密度10 kW/m^2,入口干度0.1~0.9,内螺纹铜管管径分别为5、7和9.52 mm。实验结果表明:饱和温度对冷凝压降的影响主要集中在较高的质流密度区间,压降随饱和温度的升高而降低;压降随质流密度的增大而上升,随管径的减小而增大;随着干度值的降低,冷凝压降从一个峰值开始逐渐下降,其中5 mm管的压降下降速率最大;通过对比相对传热系数得出3种内螺纹管中,5 mm管的综合性能更好。The condensation pressure drop of R404 A in micro-fin tubes was studied.In order to provide a basis for the feasibility of R404 A’s application in small-diameter heat exchanger and studying the characteristics of pressure drop rise caused by reducing pipe diameter,different influencing factors were set to study the R404 A condensation pressure drop characteristics in micro-fin tubes with outer diameters of 5,7 and 9.52 mm.The experimental conditions are as follows:saturated temperature 35~45℃,heat flux 10 kW/m^2,mass flux 200~900 kg/(m^2·s),and vapor quality 0.1~0.9.The experimental results show that,the pressure drop decreases with the increase of saturation temperature in the high mass flow range.The pressure drop increases with the increase of mass flow density and with the decrease of tube diameter.The condensation pressure drop decreases gradually from a peak value during the decrease of vapor quality,of which the drop rate is the largest for the 5 mm tube.It is concluded that the pressure drop rate of 5 mm tube is the largest by comparing the relative heat transfer coefficient.

关 键 词：小管径 冷凝压降 内螺纹管 R404A 

分 类 号：TK124[动力工程及工程热物理—工程热物理]