Empirical Study of Performance Improvement by Cylindrical Solar Still Height Utilizing a Hemispherical Dome

The shapes of solar stills have a direct effect on the behavior of these stills. In the present work, a new cylindrical solar design still covered by a hemispherical dome was fabricated. The purpose of this study is to find the effect of this modification on temperature distribution inside the still, hence, to find the effect on productivity. A steady state case of solar radiation conditions with fixed morphological conditions was used to concentrate only on the new design effect. The height of the used cylinder was increased by 10 cm in each case, starting from zero in the simple hemispherical solar still case (HSC). Changing cover design was found to play a great role in present still behavior. Temperature values decreased as cylinder height increased compared to that of HSC, while the productivity of the case of 10 cm height showed a maximum increase of 9.4% compared to that of HSC. Productivity values decreased to the maximum yield as further cylinder height was applied in the other cases. Experiments show that this new design can decrease the temperature values of all still's parts for a constant evaporation area, which makes it a suitable design for using stills with heat transfer enhancements.