Effect of inclination of the external reflector on the performance of a basin type solar still at various seasons

This paper presents an experimental investigation on the effect of internal and external reflectors inclined at angles 0° (vertical), 10°, 20° and 30° on the output of simple-basin solar stills in summer, autumn and winter. A simple still, which has a 20° cover tilt angle and equipped with internal and external reflectors is investigated at latitude angle of 33.3°N. It was found that the average daily yield is increased by the use of internal and/or external reflectors except for summer where the effect of the reflectors is found to be negative. The increase in the productivity of the still with reflector(s) compared to the still with no reflectors (increase ratio) is averaged at 19.9% and 34.5%, 34.4%, 34.8% and 24.7% for still with internal reflector only, still with internal and an inclined external reflector tilted at 0°, 10°, 20°, and 30° respectively. Accordingly, a comparable yearly productivity is expected for external reflector angle ranging from vertical to 20°. The conclusions of this study in winter agree well with the trend of the theoretical results cited in the literature at 30°N latitude angle.