Investigations on Passive Solar Liquid Desiccant Regenerator in Indoor Simulated Summer Ambient Conditions

Abstract Liquid desiccant-based air conditioning (LDAC) system is a promising alternative air conditioning system among various thermally driven cooling technologies, which can help to alleviate burden on natural resources and the earth. The regenerator of LDAC systems utilizes thermal energy to remove water from the dilute LD solution to concentrate it. The effect of weather parameters like solar insolation, wind velocity, ambient temperature and system parameters like concentration on the performance of the regenerator is investigated in terms of regeneration rate and regeneration efficiency in literature. But there is a need to establish significance of each parameter on the performance with the help of a systematic experimental study. A ‘passive solar’ regenerator indoor test set-up required for such study is developed in the current work. Experiments were designed and carried out as per DoE principles. Regression analysis of full factorial study was done to understand the effect of various parameters on performance of the passive solar regenerator. It is observed that as independent parameters, solar insolation, concentration of LD and ambient temperature have significant effect on the performance of the solar passive regenerator. The pareto chart shows that solar insolation has the most prominent and positive effect on performance. This is followed by the concentration of LD, but the effect is negative. The insights developed in current work would help decide viability of using the passive solar regenerator for a given climatic condition and deciding the concentration range to be used in LDAC systems.