受限流道沿程参数变化对竖直圆管表面结霜特性影响的实验研究  

Experimental Study on Effect of Parameter Variation along Confined Flow Path on Frosting Characteristics of Vertical Circular Tube Surface

作　　者：刘学 赖天伟[1] 赵琪 强铭琛 马斌 侯予[1] LIU Xue;LAI Tianwei;ZHAO Qi;QIANG Mingchen;MA Bin;HOU Yu(School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an 710049, China;Facility Design and Instrumentation Institute, China Aerodynamics Research and Development Center, Mianyang, Sichuan 621000, China)

机构地区：[1]西安交通大学能源与动力工程学院,西安710049 [2]中国空气动力研究与发展中心设备设计与测试技术研究所,四川绵阳621000

出　　处：《西安交通大学学报》2022年第5期149-155,共7页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(51976150)。

摘　　要：为研究换热器受限流道内沿程湿空气参数和壁温同时变化对霜层生长的影响,搭建了竖直布局的可视化结霜实验台。实验研究了受限流道内沿程霜层厚度、壁温、霜层生长率等参数的变化规律,以及逆流工况下入口湿空气温度、相对湿度、空气流速对受限流道内圆管表面的结霜量和平均霜层密度的影响。实验结果表明:沿制冷剂流动方向,制冷剂入口段霜层逐渐变薄,中间段霜层厚度趋于平坦,出口段霜层厚度上升。因受限效应的影响,在结霜初期流道内的霜层生长率逐渐降低;在结霜中期流道内水蒸气浓度随时间升高,可使霜层生长率出现小幅提升;在结霜后期霜层生长率降低。在壁温越低、水蒸气浓度越高的位置,霜层生长率出现局部增大的时间越早。更高的入口湿空气温度、相对湿度、空气流速会提升结霜量,而平均霜层密度随入口相对湿度升高而下降。To study the details of frosting in the confined flow path of the heat exchanger with the variations of humid air parameters and wall temperature along the path,a visual vertical frosting test rig is designed.The variation patterns of frost thickness,wall temperature and frost growth rate along the path are analyzed.The effects of inlet humid air temperature,relative humidity and air rate on the frost quantity and average frost density in the path are compared under the counter flow condition.The results show that along the refrigerant flow direction,the frost thickness gradually becomes thinner in the inlet section,does not change much in the middle section,and rises in the outlet section,and the frost growth rate in the path gradually decreases in the early frosting period due to the confinement effect,slightly increases in the mid frosting period as water vapor concentration in the path increases with time,and then decreases again at the final frosting period.Moreover,the lower the wall temperature and the higher the water vapor concentration,the earlier the frost growth rate increases locally,and the higher the inlet humid air temperature,relative humidity and air rate,the larger the frosting quantity.However,the average frost density decreases with the increase of the inlet relative humidity.

关 键 词：受限流道 结霜特性 霜层厚度 结霜量 平均霜层密度 

分 类 号：TK124[动力工程及工程热物理—工程热物理]