Thermal performance of desiccant-based solar air-conditioning system with silica gel coating

In the present paper, a solar-driven air-conditioning system comprising silica gel-coated concentric tube heat exchanger is fabricated and analyzed experimentally. The setup consists of two concentric tube heat exchangers with silica gel coating to achieve continuous dehumidification of the humid air. Parabolic trough-type solar collector is used as air heater to supply hot air continuously to regenerate the silica gel. The system performance is measured in terms of dehumidification factor and cooling capacity. The performance parameters are plotted against the different values of the atmospheric air temperature, cooling water temperature, and specific humidity. It is observed that the dehumidification factor and cooling capacity depend on both the cooling water temperature and the conditions of ambient air. The maximum value of dehumidification factor and cooling capacity achieved are 11.05 g/kg and 5.748 kJ/min, respectively, for the ambient air temperature of 37.6 °C and specific humidity of 23.99 g/kg.