摘要
本文研究制冷工质R404A在不同水平管管外的冷凝换热性能,实验对比了R404A在二次翅片管和斜翅管管外的凝结换热特性。这两种管的管外表面结构分别是二次翅片形和斜翅形,分析了表面结构对换热性能的影响。采用Wilson-Gnielinski图解法求解管内表面传热系数,从总传热系数中分离出管外冷凝换热表面传热系数。结果表明:二次翅片管和斜翅管的管外冷凝强化倍率分别为7.14~9.26和3.74~6.85;适当的螺纹螺旋角和螺纹间距,会产生较好的冷凝换热效果。
The condensation heat transfer performance of the refrigerant R404A outside the different horizontal tubes is studied in this paper,and the condensation heat transfer characteristics of R404A outside the two condensation-enhanced tubes are compared experimentally.The outer surface structures of these two types of tubes are secondary fin shape and oblique fin shape,and the influence of surface structure on heat transfer performance are analyzed.The Wilson-Gnielinski graphic method is used to solve the heat transfer coefficient of the inner surface of the tube,and the condensation surface heat transfer coefficient outside the tube is separated from the total heat transfer coefficient.The results show that the external condensation enhancement ratios of secondary finned tubes and oblique finned tubes are 7.14-9.26 and 3.74-6.85 respectively;proper screw angle and thread pitch will produce better condensation heat transfer effect.
作者
秦洁
欧阳新萍
丁聪
QIN Jie;OUYANG Xinping;DING Cong(School of Energy and Power Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)
出处
《制冷技术》
2020年第1期28-33,共6页
Chinese Journal of Refrigeration Technology
