制冷系统循环风量对热泵干燥除湿性能的影响

Influence of Circulating Air Volume of the Refrigeration System on Dehumidification Performance of Heat Pump Drying

热泵干燥技术因节能、环保等特点而广泛应用于木材干燥等领域,但在干燥室内湿空气相对湿度不高时,热泵干燥系统的除湿性能较差,因此通过变频器调节制冷系统循环风量,研究木材干燥过程中,不同干燥阶段循环风量对热泵干燥除湿性能的影响。结果表明:降低制冷系统循环风量可以提高系统的除湿性能。在木材干燥不同阶段,均存在一个频率值,使系统的除湿量、除湿能耗比和除湿制热性能系数达到最大值,但三者的最大值并不是都在同一个频率值下出现。随着干燥的进行,干燥室内湿空气温度升高,相对湿度降低,系统的除湿量、除湿能耗比和除湿制热性能系数随之降低;系统的除湿量、除湿能耗比和除湿制热性能系数达到最大值的频率也随之降低。

Due to the characteristics of energy saving and environmental protection,heat pump drying technology is widely used in wood drying and other fields.However,when the relative humidity of the humid air in the drying room is not high,the dehumidification performance of the heat pump drying system is poor.Through the frequency converter to adjust the circulating air volume of the refrigeration system,the influence of the circulating air volume on the heat pump drying and dehumidification performance at different drying stages during the wood drying process was studied.Experimental results showed that reducing the circulating air volume of the cooling system could improve the dehumidification performance of the system.It indicated that there was a frequency value,which maximize the dehumidification quantity,SMER(Specific Moisture Extraction Rate)and COP(Coefficient of Performance)of the system in different stages of wood drying,but the maximum value of dehumidification quantity,SMER and COP did not all appear at the same frequency value.It also indicated that the dehumidification quantity,SMER,and COP of the system decreased,and the frequency at which the dehumidification quantity,SMER,and COP of the system reached the maximum also reduced,as the drying progressed and when the temperature of the humid air in the drying room increased and the relative humidity decreased.