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Energy consumption is increasing gradually in the world. It is due to the growth of air conditioning need in response to higher summer temperatures. This causes an increase in electricity demand. Solar cooling is a relatively new, reliable and clean application of proven refrigeration technology able to improve comfort conditions, limit the impact on the environment and save energy. The use of "desiccant cooling" technique is particularly interesting because it avoids the refrigerants use that have a negative effect on the ozone layer (CFC, HCFC, HFC ...). The main element in a desiccant cooling system is the desiccator. In this study, an experimental test bed was made in the Energy and Thermal Systems Laboratory "LESTE" at National Engineering School of Monastir, Tunisia. This bench is designed to examine the optimal conditions used (air flow rates effect) for a cylindrical desiccator, filled with silica gel grains, during both adsorption and desorption phases. For this aim, measurements of temperature, humidity and velocity at the inlet and outlet of the desiccator are done.

Desiccant cooling systems are energy efficient and allow a better indoor air quality. Desiccant dehumidification is profitable in handling latent heat, easy to be reactivated with low-grade energy, like solar energy and waste heat, etc. The exploitation of heat produced by solar thermal collectors is a motivating option for thermal driven Desiccant cooling air conditioning processes. It is a good solution to guarantee less environmental impact. Desiccant cooling systems have two air streams. The first stream is the process air delivered to conditioned space, and the second stream is the reactivation air used to regenerate desiccant material. For this reason tow important phenomena are mentioned and studied: dehumidification in order to match indoor comfort criteria and humidification to produce the cooling effect. In this work, different configuration of desiccant cooling installation are studied and compared. The study focused on the cooling branch of each configuration. The principal components used in the different configurations presented are; desiccators, heat exchanger and a humidifier. The objective of this study is to evaluate the more efficient system to be used. For this aim a numerical tool was used. The reliability and efficiency of the numerical tool established was tested and validated by comparison against data collected from literature.