Modeling and Verification of Double Slope Single Basin Solar Still Using Laboratory and Actual Solar Conditions

A double slope single basin, passive type, still with basin area of 1.75 m2 is fabricated and tested under laboratory conditions. The solar radiation heat is simulated by using 2 kW electrical resistance heater placed below the inner basin. The heat supply is varied using control circuit. The still is tested for varying input condition to simulate the actual solar radiation condition with different minimum depths of water in the basin ranging from 2 cm to 0.2 cm. The experiment is also carried out at different constant input conditions with a constant depth of water. The variation of different parameters with production rate has been studied. It is found that the production rate increases with the increases of water and glass temperature. But at higher operating temperature, the production rate increases with the decrease in temperature difference between water and glass. A new model is recommended for the still with shallow basin. The experiment is also conducted with the same still at actual sunshine conditions and compared with the model. The experimental values are in close agreement with model values.