微圆管内非共沸混合物流动沸腾压降试验  

Experiment of flow boiling pressure drop of non-azeotropic refrigerant mixtures in micro-tube

作　　者：胡自成[1] 马虎根[2] 

机构地区：[1]江苏大学能源与动力工程学院,江苏镇江212013 [2]上海理工大学动力工程学院,上海200093

出　　处：《江苏大学学报（自然科学版）》2007年第5期413-416,共4页Journal of Jiangsu University：Natural Science Edition

基　　金：上海市高等学校科学技术发展基金资助项目(01F09);上海市市重点学科资助项目

摘　　要：对水平微圆管内非共沸混合工质R32/R134a的流动沸腾压降进行了试验,同时可视化观察了微圆管出口处的气泡行为.在此基础上分析了主要工况参数对微圆管内流动沸腾压降的影响,比较了微圆管、细圆管和常规管道内的两相流动压降特性.结果表明:微圆管内流动沸腾压降随质量干度和质量通量密度的增加而平稳增加.当热通量较低时,微圆管内压降增加幅度较小,但当热通量达到一定值时,微圆管内压降则以较大幅度升高.相同试验工况下微圆管内流动沸腾压降远大于常规管道.综合考虑流动压降和换热效果时,存在最佳通道结构使其换热经济性最好.Experiments were conducted to investigate pressure drop characteristics during flow boiling of non-azeotropic refrigerant mixtures of R32/R134a （mass ratio 25%/75% ） in micro-tube （0.86 mm i. d. ） of 200 mm heated length, and bubble behaviors in the exit of micro-tube were observed. Effects of mass flux, mass quality and heat flux on two-phase pressure drop in micro-tube were analyzed and com- parisons were made with mini-tube and normal-tube under the same working conditions. The results show that two-phase pressure drop in micro-tube rises with increasing mass quality and mass flux. When heat flux is lower, two-phase pressure drop increases in step with increased heat flux, but two-phase pressure drop rises with a higher value once reaching a higher heat flux. Compared with mini-tube and normaltube, two-phase pressure drop in micro-tube is much higher under the same working conditions. When considering both heat transfer enhancement and two-phase pressure drop, an optimum micro-channel configuration exists for micro-channel heat exchangers to achieve the best heat transfer economical performance.

关 键 词：两相流动压降 微圆管 非共沸混合工质 流动沸腾 试验研究 

分 类 号：TK124[动力工程及工程热物理—工程热物理]