Effect of air flow on tubular solar still efficiency

Abstract

In general, CPCs are used for steam generation and water heating processes, since they are able to produce higher temperatures than flat plate collectors. But in this study an attempt is made to use this concentrator for solar desalination. An experimental work was reported to estimate the increase in distillate yield for a compound parabolic concentrator-concentric tubular solar still. The CPC dramatically increases the heating of the saline water. A novel idea was proposed to study the characteristic features of CPC for desalination to produce a large quantity of distillate yield. A rectangular basin of dimension 2 m × 0.025 m × 0.02 m was fabricated of copper and was placed at the focus of the CPC. This basin is covered by two cylindrical glass tubes of length 2 m with two different diameters of 0.02 m and 0.03 m. Findings The experimental study was operated with two modes: without and with air flow between inner and outer tubes. The rate of air flow was fixed throughout the experiment at 4.5 m/s Conclusion On the basis of performance results, the water collection rate was 1445 ml/day without air flow and 2020 ml/day with air flow and the efficiencies were 16.2% and 18.9%, respectively. © 2013 Thirugnanasambantham et al.