Paper Title
Performance Comparison of Double Slope Solar Distillation Systems with Concave and Flat Collectors

Abstract
The performance of solar still significantly depends on its structural design including glass cover shape. The objectives of this paper are to theoretically analyze and compare the performance of double slope solar stills using flat and concave glass collectors for the weather condition of December in Mandalay. The temperatures of glass collector, water, basin and fresh water production rate for two different solar stills are theoretically calculated. In theoretical analysis, the tilt angles of glass covers are set as 45° which is optimum inclination angle to receive the highest solar heat flux in December for Mandalay. The view factor for flat cover is taken 0 and it is taken as 0.5 for concave glass collector. In still with flat glass collector, the temperatures of glass collector, water and basin can reach 37 °C, 43 °C and 44 °C respectively while 38 °C, 44 °C and 45 °C for the still with concave collector. Thus, the concave glass cover is more effective than flat cover. Keywords - performance analysis, water treatment, simulation, solar distillation, solar collector shape.