Optimisation et dimensionnement d’un système de dessalement performant

Abstract

"Solar distillation is an interesting solution for the supply of drinking water in arid and / or isolated areas. However, the production of conventional solar stills remains insufficient. Therefore, and in order to improve their production, our object consists the study of the effect of many parameters on the distillation process, especially changing the glass cover geometry, the association of the solar still to another solar devices and the number of the basin in the still. For this, a comparison of six types of solar distillation systems (single slope, double slope, spherical, still-reflector, still-collector and multi-stage solar still) was conducted. The thermal balance of the different devices has been developed and solving equations governing the operation of these systems is discussed by a numerical approach based on the Runge Kutta 4th order method. Furthermore, a companion of measurements was carried out on a spherical solar still in order to identify its operation. In addition, our interest focused on two-dimensional and laminar thermosolutal convection in a spherical solar still. The flow is modeled by the equations of continuity, conservation of momentum, conservation of energy and chemical species concentration with (Ψ, Ω) formulation in the spherical coordinate system. The numerical resolution is tackled by the finite difference method. The numerical results show the influence of various parameters (numbers, thermal Rayleigh, Lewis and buoyancy) on the heat and mass transfer within the solar still, as well as the fluid-wall heat and the mass transfer quantified respectively by Nusselt and Sherwood numbers.