Visualization on Flow Patterns during Condensation of R410A in a Vertical Rectangular Channel  

作　　者：XU Wenyun JIA Li 

机构地区：[1]Institute of Thermal Engineering, School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University

出　　处：《Journal of Thermal Science》2014年第3期269-274,共6页热科学学报（英文版）

基　　金：supported by National Natural Science Foundation of China(No.51176008);National Key Technology R&D Program(2012BAB12B02)

摘　　要：The visualization experiments on HFC R410A condensation in a vertical rectangular channel （14.34mm hydraulic diameter, 160mm length） were investigated. The flow patterns and heat transfer coefficients of condensation in the inlet region were presented in this paper. Better heat transfer performance can be obtained in the inlet region, and flow regime transition in other regions of the channel was also observed. Condensation experiments were carried out at different mass fluxes （ from 1.6 kg/h to 5.2 kg/h） and at saturation temperature 28~ C. It was found that the flow patterns were mainly dominated by gravity at low mass fluxes. The effects of interfacial shear stress on condensate fluctuation are significant for the film condensation at higher mass flux in vertical flow, and con- sequently, the condensation heat transfer coefficient increases with the mass flux in the experimental conditions, The drop formation and growth process of condensation were also observed at considerably low refrigerant vapor flow rate.

关 键 词：flow pattern CONDENSATION vertical channel heat transfer R410A 

分 类 号：TK124[动力工程及工程热物理—工程热物理]