A comparative experimental investigation of rectangular, trapezoidal, and concave basins design to augment the performance of double-slope solar distillers

Solar distillers are characterized by simple, economical, and effective ways to produce freshwater in remote and isolated regions that suffer from freshwater poverty, but suffer from low freshwater yields. So, the present comprehensive experimental study aims to get the optimal trough design that achieves the highest freshwater yield of solar distillers. To achieve this idea, the troughs were designed in the shapes of trapezoidal and concave instead of rectangular troughs to achieve the highest performance of a double-slope solar distiller. To reach this goal experimentally, three double-slope solar distillers (DSSD) were designed, built, and tested; the first is DSSD with rectangular trough (DSSD-RT), the second is DSSD with trapezoidal trough (DSSD-TT), and third is DSSD with concave trough (DSSD-CT). Experimental results show that the proposed concave trough (DSSD-CT) represents a good design that raises the accumulative diurnal distillate output to 5.8 L/m 2 day with an improvement of 64.8% compared to DSSD-RT. Also, the improvement rates in thermal efficiency, exergy efficiency, and sustainability index for utilizing the proposed concave trough (DSSD-CT) reached 63.9%, 92.7%, and 2.7%, respectively compared to DSSD-RT.