Analysis of Constructive Modifications for Enhancing the Performance of Solar Collector/Regenerators for Liquid Desiccant Systems
Abstract
The current concerns about environmental sustainability in the air-conditioning sector and reduction of energy dependence on fossil fuels in power plants towards the decrease of CO2 emissions have indeed strongly contributed to renew the interest of researchers and developers in direct solar thermally-driven liquid sorption systems, in which the diluted desiccant solution is regenerated by its simultaneous exposure to the solar radiation and scavenging air stream into a collector/regenerator (C/R), whose required large dimensions and technical difficulties for properly wetting its absorber plate limit its market penetration. To improve the heat/mass transfer within C/Rs, structural modifications based on adding an upper air-preheating channel, an artificially roughened plate and a flat bottom reflector are theoretically analysed in this paper. The results demonstrate that the air-preheating channel has a moderate impact on the water desorption rate, whereas the turbulators and the solar concentrator exhibit high potential to boost the performance of C/Rs.