Experimental Study on the Heat Transfer Capacity and Dehumidification Performance of a Parallel Flow Evaporator for a Heat Pump Dryer

Abstract In the present study, the performances of a fin-tube evaporator and three PF evaporators for a heat pump dryer were experimentally investigated. Among the tested evaporators, the PF3 type evaporator showed the highest values of heattransfer capacity and dehumidification performance, while the fin-tube evaporator had the lowest values. PF3 showed betterperformance compared to PF1 and PF2, due to the large pin pitch, which leads to more draining for dehumidified water.Also, the 45° inclined PF evaporator presented better performance than that of the 90° inclined PF evaporator, owing toits easier draining characteristics. The effect of air velocity was revealed to be quite large. When the air velocity increased by 20%, the heat transfer capacity and dehumidification performance increased 43%/11%, 48%/13% and 54%/23% for PF1,PF2 and PF3, respectively. Key words Dryer(건조기), Evaporator(증발기), Parallel flow(평행류), Dehumidification(제습), Heat pump(히트펌프)†Corresponding author, E-mail: jtkwon@hoseo.edu