Experimental and Theoretical Model for Water Desalination by Humidification - dehumidification (HDH)

This paper aims to provide both experimental and theoretical model for utilization of Fresnel lens in solar water desalination by humidification-dehumidification process. The work was done in two stages. The first stage aimed at investigating the performance of Fresnel lens in heating saline water. Solar energy is considered as a source of heating. For thermodynamic analysis, mass and energy balance equations have been developed for the water heating, humidifier, and other cycle components. The models were solved numerically and validation showed that the model outcomes are 25% higher than the experimental data due to energy losses. The analysis indicates that Fresnel lens collector has good efficiency (70%) in clear days. The influence of ambient conditions and the percent of different types of energy loss, etc., are also analyzed. The second stage was to perform experiments for intensification of fresh water yield from the unit. The experiments were done for both open and close loop of air. The results showed that closed loop system provides higher water production than open loop system.