自融霜螺杆式空气源热泵除霜过程实测分析

Measurement on defrosting process of self-defrosting screw air source heat pump

对一种使用自融霜技术的螺杆式空气源热泵系统的运行性能进行现场实测,并利用实测数据计算与分析其除霜过程。结果表明:在-8~0℃的室外温度下,除霜周期中热泵连续供热的平均COP为2.0左右,制热周期机组COP平均为3.0;当室外温度为-0.38℃,供水温度为49.5℃时,其4组室外换热器的除霜时间依次为50 s,52 s,62 s和62 s;4组室外换热器轮换除霜期间,自融霜螺杆式空气源热泵连续供热的平均制热量与其除霜开始前的制热量之比分别是69.3%,61.8%,59.4%和58.6%;压缩机排气温度在除霜时的下降幅度为4~6℃。

The operating performance of a screw air source heat pump system with self-defrosting technology is measured on site,and the defrosting process is calculated and analyzed by using the measured data.The results show that the average COP of continuous heating of the heat pump is about 2.0 in the defrosting cycle and about 3.0 in the normal heating cycle under the outdoor temperature from-8℃to 0℃;when the outdoor temperature is-0.38℃and the water supply temperature is 49.5℃,the defrosting time of four groups of outdoor heat exchangers is 50 s,52 s,62 s and 62 s respectively;during the rotation defrosting period of the four groups of outdoor heat exchangers,the ratios of the average heating capacity of continuous heating by self-defrosting screw air source heat pump to the heating capacity before defrosting are 69.3%,61.8%,59.4%and 58.6%respectively;the discharge temperature of the compressor decreases by 4-6℃during defrosting.