THERMAL PERFORMANCE OF SINGLE SLOPE DOUBLE BASIN SOLAR STILL

Man has depended on underground water reservoirs for fresh water requirements, but the use of water, from such sources is not always possible, on account the presence of salt water. Solar still is a very simple solar device used for converting available salt or waste water into potable water. A transient mathematical model was presented for a double basin solar still (DBSS). It was based on an analytical solution of the energy balance equations for the various elements of the still. Numerical calculations were performed on typical summer days in Coimbatore (11°.00 N, 77°.00 E), Indian climatic conditions. The entire portion of the still was sealed to reduce the vapor leakage to the surroundings. Hourly and daily measurements of the still productivity, temperatures of water film as well as inner and outer glass covers, ambient air temperature and solar radiation were recorded. The double basin solar still was constructed and tested during April and May 2009. A 2- month study showed that the productivity of the solar still depends on solar radiation, ambient temperature and solar orientation. The average daily output of the still in the summer 2009 was found to be 5.633 L/ m2.