【摘要】 对结霜工况下空气源热泵的动态特性进行了数值模拟,并在室外环境空气温度及相对湿度分别为-15~3℃和50%~90%范围内对一台空气源热泵空调器的动态性能进行了实验研究,测量了不同结霜工况条件下热泵空调器的动态性能参数、室外换热器结霜量及壁面温度分布.在此基础上分析了进风温、湿度对空气源热泵空调器性能的影响.实验结果表明:在室外换热器表面结霜的初始阶段,热泵系统的制热量及性能系数均有所提高,但在结霜的后期,热泵性能迅速衰减,与数值预测结果一致;对于相对湿度不同的进口空气,其温度为0~3℃时室外换热器表面结霜速度最快,在此温度范围内结霜对热泵性能影响最大.更多还原

【Abstract】 Regarding the frost accumulation on the outdoor coils as a quasi-dynamic process,the dynamic performances of an air source heat pump(ASHP) system under frosting conditions were simulated.A series of experiments on the dynamic performance of the ASHP unit under frosting conditions were conducted to verify the present simulation model.The experimental outdoor air temperature ranged from-15 ℃ to 7 ℃,and the relative humidity from 50% to 90%.The dynamic performance parameters of the ASHP system under frosting conditions,the frost mass accumulation on the outdoor coils,and the wall temperature distribution along the heat exchange tubes were measured.Based on the experimental results,the effects of the outdoor air temperature and the relative humidity on the performance of ASHP unit were analyzed.The experimental results indicate that the heating capacity and coefficient of performance of the ASHP unit increase in the initial frosting stage and decrease rapidly in the later frosting stage.These experimental results are in good agreement with the corresponding simulation ones.In addition,it is found that the frost formation rate is greatest when the outdoor air temperature is about 03℃ at different outdoor air relative humidities.更多还原