Numerical Study of a Simple Double-Slope Solar Distiller: A Sustainable and Economical Alternative

Abstract

Introduction: Faced with population growth, increasing needs for drinking water, and the scarcity of water resources in many regions of the world, the search for alternative and sustainable solutions for water production is becoming an urgent necessity. Among these solutions, solar distillation stands out as a simple, ecological, and economically viable technique, particularly for arid and isolated areas where access to fresh water is limited.

Objectives: Our work is part of a modeling and numerical analysis approach to the thermal performance of a simple double-slope solar distiller. The main objective is to evaluate the thermal behavior of the water and the absorber in this system, highlighting the effects of the configuration on the efficiency of the distillation process and, more specifically, on the quantity of water recovered.

Methods: The method chosen in our work is based on 3D geometric modeling using SolidWorks software, then integrated into the COMSOL Multiphysics simulation environment, which allows for multiphysics analysis of heat and moisture transfer phenomena. This numerical approach provides a detailed view of temperature evolution and a better understanding of the influence of the distiller's simple double-slope structure on the system's energy efficiency.

Results: In this study, we used COMSOL Multiphysics software to simulate and analyze the fundamental physical phenomena within a simple, double-slope solar still. We focused particularly on studying heat transfer in the water and the absorber, neglecting other areas of the system. The still under study is a simple, static system with no water flow; the water remains stationary in the basin. This configuration allowed for a more direct study of heat transfer between the different parts of the still (absorber and water). This simplicity facilitated the analysis of the thermal behavior and the evaluation of the device's energy performance. The numerical results confirm the system's efficient thermal operation, which is physically confirmed by the effective conversion of solar energy into heat, thus promoting water evaporation. Even when stationary, the water heats up, generating steam that then condenses to form distilled water. This process is primarily due to heat transfer by conduction, natural convection, and radiation within the device.

Conclusions: This work is part of the development of sustainable solutions for producing drinking water from solar energy. Through a numerical approach combining geometric modeling in SolidWorks and multiphysics simulation in COMSOL Multiphysics, we studied the thermal behavior of a simple configuration: a simple double-slope solar still. We investigated the variation of several parameters over the course of the tests. In conclusion, this numerical study makes a significant contribution to the understanding of thermal phenomena in solar stills. It also provides a solid foundation for the design, optimization, and construction of experimental prototypes, within the framework of promoting renewable, economical, and sustainable technologies in the field of water treatment and drinking water supply in regions currently suffering from water scarcity due to pollution, climate change, overpopulation, and the misuse of resources. A large part of the planet lacks water, a resource essential to life.