热泵干燥系统性能试验研究

设计了一套热泵干燥装置，压缩机3.73 kW，制冷工质为R22，并在此试验装置上进行了热泵干燥系统的性能试验。试验结果表明，在开路式热泵干燥运行时，蒸发器析水速率较低，但热泵运行稳定；而在半开路式热泵运行时，随着外排干燥废气的减少，蒸发器析水速率不断增加。闭路式热泵干燥循环过程中，空气旁通率(BAR)对热泵的运行状况影响较大。开路式、半开路式热泵干燥循环中，系统的单位能耗除湿量较高。在闭路式热泵干燥循环过程中，当BAR=0.4和BAR=0.6时， 系统的单位能耗除湿量有最大值。

Experimental study on the performance of heat pump drying system

In the present study, a heat pump dryer was designed and manufactured, its refrigerant was R22.The performance of opening air cycle, semi-opening air cycle and closed air cycle configurations was studied. When the heat pump works with the opening air cycle, the heat pump unit works in the steady state and extraction water from the process air is lower than that with the semi-opening air cycle. When the heat pump works with the semi-opening air cycle, the extraction water from the process air will increase by exhausted air loss. In the closed system, the bypass air rate(BAR) plays a significant role in the system performance. As BAR increases, the amount of air passing the evaporator is reduced and the BAR directly alters the HPD performance. The extraction water from the process was not sensitive to BAR values within the range from 0.4 to 0.7. To obtain the peak of SMER, the system should be operated with BAR between 0.4 and 0.6. With BAR greater than 0.6, the peak values seem to be reduced. It was, therefore, concluded that the bypassing air rate(BAR) was effective at the maximum SMER.