Performance enhancement of pyramid-shaped solar stills using hollow circular fins and phase change materials

The pyramid solar still has bulky condensing and receiving surface area in compared to the conventional single slope solar still. The present study concerns experimentally with the performance enhancement of this pyramid solar still via additional performance improvers. Hollow circular copper fins array are fitted at the absorber plate in addition to PCM tank below the absorber surface to extend the water production time after the sunset. To obtain the influences of hollow circular fins and PCM on the performance of the pyramid solar still. In the experimentations, the conventional pyramid solar still, pyramid solar still with hollow circular fins, and pyramid solar still with hollow circular fins and PCM were tested at the same Egyptian weather conditions. Saline water depth of 2 cm is hold constant within the basin via compensate feed saline water tank. The experimental results show that, the conventional pyramid solar still gives maximum productivity of 4.02 L/m(2)/day while the hollow fins utilization enhances the productivity to 5.75 L/m(2)/day with 43% enhancement in the daily productivity. The PCM addition augments the productivity to 8.1 L/m(2)/day representing 101.5% enhancement in the daily productivity. Comparison between the present modified pyramid solar still and previous experimental and theoretical studies shows efficient performance of the present modified hollow circular fins and PCM pyramid solar still.