翅片管冷凝器低压环境下空气侧换热特性研究  

Study on the Characteristics of Air Side Heat Transfer for Finned Tube Condenser in Low-pressure Environment

作　　者：张汝行 柳建华[1,2] 张良 Zhang Ruhang;Liu Jianhua;Zhang Liang(College of Energy and Power Engineering,University of Shanghai for Science and Technology, Shanghai, 200093, China;Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering, 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 [2]上海市动力工程多相流动与传热重点实验室,上海200093

出　　处：《制冷学报》2021年第1期99-104,共6页Journal of Refrigeration

基　　金：上海市部分地方院校能力建设专项计划项目(16060502600)资助

摘　　要：本文通过搭建压力可调的封闭环境仓,实验研究了在40~101 kPa低压环境下,不同的管排数和循环热水温度对翅片管冷凝器空气侧对流换热特性的影响。结果表明:在相同的空气侧雷诺数下,环境压力的降低导致空气侧对流换热减小。当空气侧雷诺数为400时,环境压力从101 kPa降至40 kPa,对流换热表面传热系数随之降低44.1%;随着环境压力的降低,管排数对空气侧对流换热的影响变弱;在低压环境下,改变循环热水温度不会对对流换热表面传热系数产生明显影响。随着环境压力的降低,空气侧的对流换热表面传热系数与常压模型的计算结果偏差增大,当环境压力从101 kPa降至40 kPa时,平均偏差从17.3%增至77.5%。在实验的基础上,本文根据环境压力、管排数对空气侧对流换热的影响,对常压下的翅片管空气侧换热模型进行修正,修正后的平均偏差为9.5%。In this study,a pressure-adjustable closed environment chamber was built,and the effect of different tube rows and circulating hot water temperatures on the characteristics of air-side convective heat transfer for a finned tube condenser at a low-pressure environment of 40-101 kPa were studied.The results show that under the same Reynolds number,the reduction in ambient pressure leads to a reduction in air-side convective heat transfer.When the air-side Reynolds number is 400,the ambient pressure decreases from 101 kPa to 40 kPa,and the convective surface heat transfer coefficient decreases by 44.1%.As the ambient pressure decreases,the number of tubes has a weaker effect on the air-side convective heat transfer.In a low-pressure environment,changing the heating temperature of the circulating water does not have a significant impact on the convective surface heat transfer coefficient.As the ambient pressure decreases,the air-side convective surface heat transfer coefficient deviates from the calculation results of the normal atmospheric pressure model.As the ambient pressure decreases from 101 kPa to 40 kPa,the average deviation increases from 17.3%to 77.5%.Based on the experiment results,the air-side heat transfer model of the finned tube at normal pressure is modified according to the influence of the ambient pressure and the tube rows on the air-side convective heat transfer,and the average deviation is 9.5%.

关 键 词：翅片管冷凝器 低压环境 对流换热 雷诺数 

分 类 号：TB611[一般工业技术—制冷工程] TK172[动力工程及工程热物理—热能工程]