Theoretical modeling of Solar Still with water cooled Integrated Built-in Condenser

Abstract

Fresh water demand is growing every day in the world. Solar desalination using a still has been regarded as the sustainable solution in particular in rural and arid areas. Investigations and research has focused on exploring theoretical methods and finding ways to simplify the design process of solar stills. This research is essentially a theoretical approach focused on the effect of a water cooled passive built-in condenser incorporated into a conventional solar still daily productivity. The condenser plate is cooled by water falling film evaporation process to the surrounding air. Two approaches were studied; (1) a steady state water falling film and (2) a transient water falling models. It has been found that the condenser plate and the interface between the water film and the surrounding air temperatures deviate by a maximum of 4.7%. Also the deviation of accumulated daily production rate is 4.8%. Using water cooling, the daily production rate for the glass cover drops by 52% and increases for the condenser by 110% and the total production rate has increased by 9.3%.