R134a在7 mm强化管内的冷凝传热特性  

Condensation Heat Transfer Characteristics of R134a in Enhanced Tubes with outside Diameter of 7 mm

作　　者：毛舒适 陶乐仁[1] 李庆普[1] 吴生礼 张丹亭 MAO Shushi;TAO Leren;LI Qingpu;WU Shengli;ZHANG Danting(School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China)

机构地区：[1]上海理工大学能源与动力工程学院,上海200093

出　　处：《制冷技术》2018年第5期30-34,共5页Chinese Journal of Refrigeration Technology

基　　金：上海市动力工程多相流动与传热重点实验室开放基金(No.13DZ2260900)

摘　　要：为了研究内螺纹管齿型参数、冷凝温度和质流密度等对管内R134a换热特性的影响,本文对2根外径为7 mm的螺纹管在无润滑油干扰时、不同冷凝温度下(35℃、40℃和45℃)进行了冷凝实验,探索了冷凝温度、螺旋角和质流密度对换热特性及压降的影响。实验结果表明:螺旋角为28°换热管(瘦齿、大螺旋角管)的单位压降冷凝传热系数(h_r/ΔP)比螺旋角为18°换热管(普通管)高约11.5%～27.8%,综合性能提升明显。To investigate the effects of micro-fin geometries, condensation temperatures and mass flux on the condensation characteristics of R134a inside tube, two kinds of inner-grooved tubes with outer diameter of 7mm were tested at different condensing temperatures (35 ℃, 40 ℃ and 45 ℃) without the interference of lubricating oil. The effects of condensing temperatures, helix angle and mass flux on heat transfer characteristics and pressure drop were investigated. The experimental results show that the condensation heat transfer coefficient per unit pressure drop (hr/ΔP) of the tube with a helix angle of 28° is about 11.5%~27.8% higher than that with a helix angle of 18°, and the comprehensive performance is improved obviously.

关 键 词：螺纹管 螺旋角 齿顶角 传热系数 压降 冷凝温度 

分 类 号：TK124[动力工程及工程热物理—工程热物理]