Modeling and performance of a two-stage collector/regenerator for solar liquid desiccant air conditioning system
A two-stage collector/regenerator (C/R) for the solar liquid desiccant air conditioning system is presented, which adopts a fin-forming absorber plate and where the liquid desiccant flowing process is divided by an isolation board into two stages: regenerating stage I and regenerating stage II. Then a heat and mass transfer mathematical model is established to predict the performance of the two-stage C/R by using calcium chloride as the desiccant. The main results are as follows: (i) The fin-forming absorber plate can increase heat and mass transfer areas and promote turbulence, so that it significantly enhances heat and mass transfer between solution stream and air stream; (ii) Compared with the traditional C/R, a 10 to 25 percent increase in the water evaporation rate for the two-stage C/R can be achieved under the same operating condition.
An experimental study of a forced flow solar collector/regenerator using liquid desiccant
One of the main components of a liquid desiccant cooling system is the regenerator. In a liquid desiccant air conditioner, outside air is dehumidified by liquid desiccant and cooled within the absorber. The diluted desiccant solution thus obtained has to be concentrated for reuse, by passing through the regenerator and the cycle is, consequently, repeated. The regenerator used in this application is a forced parallel flow type solar collector/regenerator. The regenerator has been designed and optimized and the prototype of the solar collector/regenerator has been built and tested. Calcium chloride has been used as the absorbent solution. The results of the tests conducted as a parametric analysis indicate that the air and solution mass flow-rates and the climatic conditions affect the regenerator performance. Furthermore, a comparison between the experimental data obtained and a previously developed model for a forced parallel flow solar collector/regenerator reveals that the experiments are in good agreement with the model predictions. Finally, it was concluded that the proposed solar collector/regenerator performs satisfactorily under the summer conditions of Adelaide, Australia.
On a New Subclass of p-Valent Close-to-Convex Mappings Defined by Two-Sided Inequality
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