The Purpose of the paper is studied three types solar distillers, double slope with and without immersed fins and the simple solar distiller. A monthly comparative study is investigated experimentally, for a long period of the year. Further, the wind speed influence, the distance between fins, the fins height, the fins number and thickness, on the solar distiller’s production, is investigated theoretically. From the obtained results, it is noted that for the wind speed greater than 3.5 m/s, a decrease in the productivity is caused by the cooling of the outer walls, and this induces some heat losses, especially at the front and rear walls of the solar still. The distance between fins has no significant effect on the still productivity. Moreover, increasing the fins height, from 2 to 5 cm, increase the productivity; however, when the height changes from 6 to 8 cm, the distillate production goes down. A larger fins number lead for rise the produced distilled water amount. Therefore, one should use the maximum number of fins, while taking into consideration the feasibility of the assembly. Increasing the water mass makes the productivity to go down. The obtained results on June 11, 2016, show that the proposed system productivity was about 15 to 27 % higher than that of a simple one, under the following conditions, i.e. Mw = 42.61 kg, h1 = 3.6 cm, Vw = 3.5 m/s, lw = 5 cm and Nfins = 12. The total annual cost estimation proof clearly that the payback period is less than a years. As well as, it has been found that the increasing lifetime and the interest rate decreasing caused a decrease in the distilled water unit price.
solar still, distilled water, shadow, immersed fins, solar irradiation flux
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