Wind direction effect on the thermal performance of the single‐slope solar still

Abstract Wind direction is one of the most critical factors to consider when examining the heat transfer characteristics of any solar–powered device. However, this parameter has been neglected in solar desalination analysis, as the external heat loss over the distiller's glass cover was evaluated solely based on ambient temperature and wind speed. This study investigates the influence of wind direction on the thermal performance and productivity of the single‐slope conventional solar still (CSS). The wind–induced heat transfer coefficient ( h w ) on the still's glass cover was evaluated through indoor conditions. Experiments were conducted for three main wind flow directions, according to the distiller position (headwind, side wind, and tailwind). For each direction, the wind speed was varied from 1 to 3 m/s. Results show that the wind direction highly affects the distiller's thermal behavior and productivity. The h w is highest when the wind blows facing the distiller, whereas it decreases by about 7% when the wind blows on both sides of the distiller and by 46% when the wind blows from the back side. Similarly, ṁ d is highest when the still glass cover is windward and decreases by 7.36% when the wind blows on both sides and by about 17.8% when the glass cover is leeward. Based on the findings, a new correlation for both h w and ṁ d , as a function of wind speed and direction, was proposed for the single–slope CSS.