Analysis of thermal performance and collector efficiency of solar distillation system with modified absorber surface shape

Abstract

Solar distillation is an environmentally friendly technology that is effective for addressing the clean water crisis; however, its performance is often limited by the low heat transfer rate on the absorber plate. This study aims to analyze the effect of variations in absorber geometry (flat plate, and U-corrugated) on the water temperature profile, cumulative freshwater productivity, and collector efficiency in a solar distillation system. Experimental testing was conducted from 10:00 to 14:00. The results indicate that modifying the absorber geometry significantly enhances thermal performance. The U-corrugated absorber recorded the highest water temperature of 59.9 °C at 12:00, coinciding with the peak solar radiation intensity. Furthermore, the U-corrugated absorber produced the highest cumulative freshwater yield, reaching 895 mL at the end of the testing period (14:00), and the flat plate (705 mL). In terms of thermal collector efficiency, the U-corrugated type achieved the highest efficiency of 33.6% at 13:00. The enlarged surface area of the absorber and the enhanced fluid turbulence induced by the U-corrugated geometry were proven to accelerate the evaporation rate. Overall, the utilization of a U-corrugated absorber represents geometric strategy for enhancing heat energy transfer and maximizing the productivity of solar water distillation systems.