Mathematical modeling of an integrated system for regeneration of solid desiccants using a solar parabolic dish concentrator

In this work, an integrated system is introduced to regenerate the desiccant materials in solar air conditioning systems. A solar parabolic dish collector and a helically baffled cylindrical cavity receiver were coupled to two series finned-tube heat exchangers, and a fixed bed filled with silica gel. A silicone oil as heat transfer fluid absorbs the solar energy and heats the air to regenerate the silica gels in the bed. The system was studied both experimentally and theoretically. A comprehensive mathematical model was developed for the entire system, and the proposed model was validated with experimental data. The regeneration rate of the desiccant materials and the average daily thermal regeneration efficiency of the system were obtained up to 0.4 kg water/h m(2) and 30% respectively, which compared to the other solar systems, the present system has a good performance and is more efficient. Based on the weather conditions of the installed location of the system, the operational or even geometrical parameters of the system can be designed in such a way that for specified required cooling capacity, the system can provide the required energy for regeneration of desiccant materials. The system performance was studied during a sample day based on real solar irradiation intensity and ambient conditions, and the influence of the effective parameters was investigated on the regeneration rate of the silica gels. (C) 2019 Elsevier Ltd. All rights reserved.