An experimental investigation of the effectiveness of partially and fully submerged metal hollow-fins and jute cloth wick-fins on the performance of a dual-basin single-slope solar still

Abstract

The rapid growth of the population and industrialization have caused a global crisis for potable water, which has triggered researchers to propose an alternative solution to the problem. Solar still is a solar energy-based device confronting the problem of low productivity. The prime objective of the present study is to investigate the effectiveness of hollow-fins and wick-fins on the performance of dual-basin single-slope solar still. The performance of solar still with hollow-fins, wick-fins, and without fins has been compared in two sets of experiments for partially and fully submerged cases. The distillate outputs from stills for partially submerged fins were 4.2313 L/m2 (8.96% higher) with wick-fins, 4.0733 L/m2 (4.89% higher) without fins, and 3.8833 L/m2 with hollow-fins. The wick-fins improve the performance of the solar still by increasing the evaporation surface and rate of evaporation through capillary action. The distillate outputs from stills for fully submerged fins were 3.6554 L/m2 (3.91% higher) with wick-fins, 3.8534 L/m2 (9.54% higher) without fins, and 3.5179 L/m2 with hollow-fins. The reason for the higher performance of still without fins are the highest temperature of the lower basin; reduced heat loss due to increased heat storage capacity of brackish water; a lower temperature difference between the lower basin and saline water that increases evaporation of brackish water in the lower basin; the highest temperature difference between saline water and the upper basin glass cover that enhances the condensation rate of water vapour in the upper basin. The still with wick-fins proved to be the most efficient from the performance and economic point of view for partially submerged fins, while the still without fins proved to be the most efficient for fully submerged fins.