Paper Title
Simulation Study for Identifying the Optimum Cover Inclination for Solar Still Systems

Abstract
Solar desalination is one of the most necessary research lines due to fresh water scarcity. One of the most famous technologies used for water desalination is solar stills. In these solar still, normally a glass cover is used for water vapor condensation and for passing solar radiation inside the still. The inclination of this glass cover is an important parameter. If this inclination is large, the vapor space increases and the condensation rate decreases. However, if the inclination is smaller than a specific value, the water droplets get back to the basin without collecting in the fresh water passage. For that reason, this simulation study is presented to find the optimum inclination angle necessary for the glass cover. In this simulation, volume of fluid method with level set is applied in ANSYS Fluent software. In this study a 3D model was created and a water droplet was applied with adhesion force on the glass. The angle of the glass is changed gradually to find the minimum inclination angle at which the water drops of different sizes will slide on the glass cover and not dropped back to the basin. It was found that for the angles larger than 15o, the droplet slides over the surface without separation. Keywords - Solar Still, Computer Simulation, Water Desalination