【作者】 范晨； 梁彩华； 江楚遥； 汪峰；

【Author】 Fan Chen;Liang Caihua;Jiang Chuyao;Wang Feng;School of Energy and Environment,Southeast University;

【机构】 东南大学能源与环境学院；

【摘要】 为研究空气源热泵的结霜与除霜特性,建立了热泵系统结霜动态模型和显热除霜模型,对结霜工况下的系统性能及除霜特性进行了模拟,获得了结霜过程中霜层质量与厚度,COP、制热量等参数的变化规律和除霜过程中融霜时间、滞留水质量及管壁温度的变化规律。结果表明,结霜时:初期霜层对系统性能影响较小,当结霜时间达到70min时,系统性能出现较大衰减,系统COP,制热量和蒸发压力降幅分别为6.9%,10.9%和12.3%,随着霜层的继续生长,系统性能急剧下降;除霜开始后,管壁温度迅速升高,霜层预热后进入融霜阶段,从蒸发器入口微元到出口微元段,融霜时间从7s增加到52s;进入融霜水蒸发阶段后,管壁温度增速减慢,入口微元段在77s后蒸发完毕进入干热,中间微元段和出口微元段蒸发时间依次增加;随着管壁温度升高,当换热器的散热与得热维持平衡时,管壁温度维持恒定。更多还原

【Abstract】 A dynamic frosting model of air source heat pump system and a sensible heat defrost model is built to investigate the performance of air source heat pump under frost conditions and the defrosting characteristics.The variation of the quality and thickness of frost,COP,heating capacity and evaporating pressure under frosting and the defrosting time,quality of defrost water,and wall temperature under defrosting is obtained.The results show that at the early stage of frosting,the frost has a slight effect on the system performance,when the frosting time reaches 70 minutes,the decline of COP,heating capacity and evaporating pressure reaches 6.9%,10.9%and12.3%,respectively.With the frost rising,the performance of system reduced rapidly.When defrosting,with the wall temperature rising,the frost change into defrost stage after preheat,the frost time of inlet section and outlet section increased from 7 seconds to 52 seconds.In the evaporation stage,the inlet section change into dry-heat stage after 77 seconds,the evaporate time of middle section and outlet section increased sequentially.When the exchanger’ s heat gain and loss maintained balance,the wall temperature kept constant,at last.更多还原