Abstract
Two designs of rotating wick solar stills are investigated under the same operating conditions. The first design is a called L-RWSS, where the wick belt of black jute cloth is designed to be rotated inside the solar still in a path of an “L” character. The second design is called LC-RWSS, where the wick belt is designed to be rotated in a path of an “L” character with a chamfer at the bottom end. The rotation of the wick belt is under ON time of 5 min and different OFF times (zero, 10, 20, 30, 40, 50, and 60 min). In addition, the effect of using quantum dots nanofluid on the performance of LC-RWSS is studied. Results revealed that the optimum thermal performance of LC-RWSS is obtained at 30 min OFF time either with or without nanofluid. Besides, the total accumulated daily productivity of LC-RWSS is higher than that of L-RWSS by 19% and 17% with and without nanofluid, respectively. The productivity of L-RWSS and LC-RWSS reached 8200 and 9600 mL/m2.day, respectively. The thermal efficiency of LC-RWSS is 88 and 86% with and without nanofluid respectively compared to 82% for L-RWSS under 30 min OFF time. Moreover, the cost of distilled water from LC-RWSS and L-RWSS is 0.019 and 0.022 $/L, respectively.