环境参数对空气源热泵蒸发器表面霜层影响研究  

Effect of Environmental Condition on Evaporator Surface Frost Layer for Air Source Heat Pump

作　　者：郭宪民[1,2] 王善云[1] 汪伟华[1] 陈纯正[2] 

机构地区：[1]天津商业大学天津市制冷技术重点实验室,天津300134 [2]西安交通大学能源与动力工程学院,西安710049

出　　处：《西安交通大学学报》2011年第3期30-34,101,共6页Journal of Xi'an Jiaotong University

基　　金：天津市应用基础研究计划资助项目(06YFJMJC05500)

摘　　要：对一台空气源热泵翅片管蒸发器表面结霜特性进行了实验研究,分析了室外环境温度和相对湿度对霜层的形态、平均密度、总平均密度及动态密度的影响.实验结果表明:室外环境温度的降低或相对湿度的增加将促使换热器表面霜层在生长过程中形成针状霜晶,乃至形成绒状霜层;在高温、高湿度工况下,霜层表面出现凝结水滴,使得霜层密度增大.在霜层减速生长段,霜层平均密度随结霜时间呈增大趋势,而在霜层加速生长段,霜层平均密度随结霜时间迅速减小,且动态霜层密度远远小于霜层平均密度.对环境参数不同而霜层厚度相同的霜层平均密度进行比较发现,其随环境温度的升高及相对湿度的减小而增大,且相对湿度的影响在低湿度工况下更为显著.The frosting characteristics on the surface of the hn-tube evaporator oI an air source heat pump （ASHP） were experimentally investigated. The effects of the outdoor air temperature and humidity on the frost morphology and the average density, total average density, and dynamic density of the frost layer were analyzed. The experimental results indicate that the decrease in the outdoor air temperature or the increase in the relative humidity results in the formation of the acerose-shaped ice crystals, even of the fluffy frost layer on the evaporator surface of the ASHP. At higher air temperature and humidity, the average frost density rises clearly due to the existence of the water droplet on the frost layer surface. In the deceleration stage of the frost growth, the average frost density increases with the frosting time. In the acceleration stage of the frost growth, the average frost density decreases rapidly with the increase in the frosting time and the dynamic frost density is much lower than the average density of the frost layer. The comparison between the average frost densities at the same frost layer thickness under different environmental conditions shows that the average frost density increases with the increase in the ambient temperature and the decrease in the relative humidity, and the influence of the relative humidity under the low humidity condition is more significant.

关 键 词：空气源热泵 结霜 霜层密度 霜层生长特性 

分 类 号：TB65[一般工业技术—制冷工程]