EXPERIMENTAL STUDIES ON THE EVAPORATIVE HEAT TRANSFER CHARACTERISTICS OF CO2/PROPANE MIXTURES IN SMOOTH AND MICRO-FIN TUBES WITH DIAMETER OF 5 mm
Because of environmental issues caused by CFC, HCFC or HFC refrigerants, new alternative refrigerants have gained a significant attention. In-tube evaporation heat transfer characteristics of CO2/propane mixtures were experimentally investigated and analyzed at several conditions of mass fluxes, heat fluxes, compositions of CO2/propane refrigerant mixtures and tube geometry. Heat transfer coefficient data during evaporation process of CO2/propane mixtures were measured for 5 m long smooth and micro-fin tubes with outer diameters of 5 mm. The tests were conducted at mass fluxes of 318 to 530 kg/m2s, heat fluxes of 12 to 20 kW/m2 and for several mixture compositions (100/0, 75/25, 50/50, 25/75, 100/0 by wt％ of CO2/propane). The differences of heat transfer characteristics between smooth and micro-fin tubes for various compositions of CO2/propane refrigerant mixtures and the effect of mass flux, heat flux, and evaporation temperature on enhancement factor (EF) and penalty factor (PF) were presented.
Jin Min CHO Jae Seung LEE Yong Jin KIM Min Soo KIM
School of Mechanical and Aerospace Engineering, Seoul National University Seoul 151-744, Korea
国际会议
The 22nd International Congress of Refrigeration(第22届国际制冷大会)
北京
英文
2007-08-21（万方平台首次上网日期，不代表论文的发表时间）