Performance Evaluation of Passive Solar Still with ZnO Nanoparticles in Summer and Winter Season

Abstract

AbstractThe objective of the paper is to carried out the performance analysis of the passive solar still (SS) with ZnO nanoparticles and without nanoparticles in winter and summer season. Effect of nanoparticles on the internal heat transfer coefficient (HTC) of passive SS has been analyzed and compared with the performance of SS without any nanoparticles. Experimentation is carried out in the month of January and July 2021, at MITS, Gwalior campus. The experimental analysis is performed at 4 cm water depth and at 11°, 26°, and 41° tilt angle of condensing cover with and without nanoparticles. SS with high nanoparticles (ZnO) gives better performance than without nanoparticles (plain water). In winter season, the highest 55.59 W/m2°C evaporative HTC was obtained with ZnO nanoparticles at tilt angle of 41°, whereas without nanoparticles, the maximum evaporative HTC was 19.59 W/m2°C. The highest evaporative HTC was achieved by 11° tilt angle of glass cover in the summer season, maximum evaporative HTC of 68.07 W/m2°C with ZnO nanoparticles and 30.44 W/m2°C without nanoparticles. It has been observed that ZnO nanofluids and plain water-based SS give maximum 1950 mL/m2day and 1420 mL/m2day distilled water in a day, respectively, at 41° tilt angles in winter season while in summer SS with ZnO nanofluids and plain water achieved maximum 3350 mL/m2day and 2305 mL/m2day of fresh water at 11° tilt angles of glass cover, respectively. It has been noted that performance of SS is remarkably increased with nanofluids as compared to water without nanoparticles.KeywordsSolar stillDistillationNanoparticlesHeat transferFresh water