Effect of Climatic Parameters on the Performance of Different Designs of Stepped Type Solar Still

The thermal performance of the stepped type solar still is affected by design, climatic and operational parameters. The design parameters affecting the performance of a stepped type solar still are depth of water, thickness of glass cover, insulation thickness, condensing cover material, shape of the absorber surface, absorbing material provided over the basin surface, angle of inclination of the still, enhancement of heat transfer etc. The climatic parameters include solar intensity, ambient temperature and wind velocity. The effect of various climatic parameters listed above on the distillate yield of different designs of stepped type solar stills is presented in this paper. In this work, four number of stepped type solar stills with different designs have been selected for studying the effect of climatic parameters like solar intensity, ambient temperature and wind velocity. The absorber area of each stepped type solar still is 0.5093 m2. After conducting experiments for the different designs of stepped type solar still, it has been observed that the intensity of solar radiation goes on increasing from the morning hours with maximum occurring at noon and then it goes on decreasing in the afternoon hours. The hourly variation in ambient temperature follows the same trend as that of solar intensity. It has been observed that the distillate yield increases with increase in solar intensity and ambient air temperature. Also it has been observed that as the wind velocity over the solar still increases, the distillate yield of the solar still increases continuously.