Improving the performance of tubular solar still using rotating drum Experimental and theoretical investigation

In the current work, we introduced, experimentally and theoretically, a modified technique of reducing the water depth as much as possible inside the tubular solar still using a rotating drum. The existence of the rotating drum inside the tubular solar still provides the lowest amount of basin water and creates a thin water film, which is evaporated quickly. So, the effect of using closed ends drum and open ends drum on the performance of tubular distiller was investigated. Besides, using the rotating drum increased the evaporative and exposure surface areas inside the tubular solar still. Moreover, the effect of different rotating speeds (0.02, 0.05, 0.1, 0.2, 0.5, 1.0, 2.0, 3.0, and 4.0 rpm) on the performance of tubular distiller was investigated. Furthermore, the system was studied with and without wick. The results revealed that the speed of 0.05 and 0.1 rpm obtained superior performance of tubular drum distiller with and without wick, respectively. In addition, at 0.1 rpm and without wick, the productivity of the tubular drum still was improved by 121 % and 136 % for the closed ends and open ends drums, respectively. While, at 0.05 rpm and with wick, the productivity of the tubular drum still was enhanced by 140 % and 175 % for the closed ends and open ends drums, respectively. Furthermore, with wick, the thermal and exergy efficiencies of the tubular drum still were 56.4 % and 3.45 % for the closed ends drum and 61 and 3.6 % for the open ends drum, respectively. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.