Enhancement of distillate output of double basin solar still with vacuum tubes

In this research paper, attempts are made to make a double basin solar still. the overall size of the lower basin used is 1006 mm x 325 mmx 380 mm and the outer basin is 1006 mm x 536 mm x 100 mm. black granite gravel is used to increase the distillate output by reducing the quantity of brackish or saline water in both basins. several experiments have been conducted to determine the performance of a solar still in climate conditions of mehsana (latitude of 23°59' and longitude of 72° 38'), gujarat. here, three conditions used to determine the performance of double basin solar still like a double basin solar still alone, double basin solar still with black granite gravel, double basin solar still with vacuum tubes and double basin solar still with vacuum tubes and black granite gravel. experimental results and comparison with other researchers show that, the daily distillate output increases by coupling vacuum tubes and by coupling vacuum tubes and black granite gravel to 56% and 65% respectively.