Experimental investigation on solar powered desiccant coated heat exchanger humidification air conditioning system in winter

Abstract

In this paper, a desiccant coated heat exchanger (DCHE) system driven by solar energy is built and tested under winter condition. The purpose of this experimental research is to explore the heating and humidification performance of DCHE system. Effects of hot water temperature, hot water mass flow rate and regeneration air flow flux are discussed as vital factors impacting system performance. Results show that increasing of heat water temperature as well as of hot water mass flow rate both have positive effects on humidification capacity and thermal coefficient of performance (COP) of the DCHE system. Moreover, the latter has a more remarkable influence. When a tradeoff is made between the performance of DCHE system and the thermal comfort of supply air, 40 °C and 0.4 kg/s are selected as optimum hot water condition. Under this operation condition, average humidity ratio of supply air is 5.15 g/kg, almost twice of ambient air. COP can reach 1.78 with a comfortable average temperature of supply air (28.3 °C). To provide a better supply air state under low humidify ratio of ambient air, small regeneration air flow flux is implemented, which effectively increases the humidity ratio of supply air with the decrease of COP.