Water depth effect on energy, exergy losses, and exergy efficiency of solar still with wick materials: an experimental research.

Abstract

This study analyzes the energy and exergy destruction of a solar still with black painted wick materials (SS with BPWM) at different salt water depths (Wd) of 1, 2, and 3 cm. The coefficients of heat transfer for evaporative, convective, and radiant heat transfer have been calculated for a basin, water, and glass. The thermal efficiency and exergy losses caused by basin material, basin water, and glass material were also determined. An SS with BPWM at Wd of 1, 2, and 3 cm has produced a maximum yield of 0.4, 0.55, and 0.38 kg per hour, respectively. An SS with BPWM at Wd of 1, 2, and 3 cm has produced a daily yield of 1.95, 2.34, and 1.81 kg, respectively. From the SS with BPWM at Wd of 1, 2, and 3 cm, respectively, daily yields of 1.95, 2.34, and 1.81 kg were obtained. The highest exergy loss of the glass material, basin material, and basin water for the SS with BPWM at 1 cm Wd was 728.7, 133.4, and 123.8 W/m2, respectively. The SS with BPWM's thermal and exergy efficiency are 41.1 and 3.1% at 1 cm Wd, 43.3 and 3.9% at 2 cm Wd, and 38.2 and 2.9% at 3 cm Wd, respectively. The results show that compared to the exergy loss of basin water in SS with BPWM at 1 and 3 cm Wd, the basin water exergy loss of SS with BPWM at 2 cm Wd is minimal.