Design, fabrication and modeling of a new solar still desalination system and evaluation of its performance

In this study, a new solar water desalination system is designed and fabricated. In this system, solar energy intensity has been concentrated by means of parabolic trough collector, which reflects the sunrays to its focal line, where the still is located. Performance of the desalination system was studied in real conditions. The effect of adding steel sponge to the water inside the still and the use of a canopy on the condenser fins has been studied. Results show that the performance of the desalination system increase by 17.7% and 6.3% by using steel sponge and canopy, respectively. In order to investigate the effect of various factors on the performance of the present desalination system, a thermal model is developed based on the conservation of energy. The governing equations are implemented and solved numerically in MATLAB software. Then results of this modeling, including water temperature, adsorbent plate temperature and rate of fresh water production were compared with empirical data and a good agreement between them was observed. Average relative error between experimental and thermal model results for all variables was less than 6 percent. Finally, the model is used to study the behavior of the machine in different seasons.