A new design of solar water heater

This investigation presents a new. design of solar water heater as a pyramid shaped frustum. The proposed design is a compact system in which collectors and a water storage tank are integrated together into one unit. The concept of using the frustum of pyramid as an external shape for collecting the solar radiation and as a container for hot water storage tank are presented. The frustum of pyramid solar water heater has five surfaces, four surfaces represent liquid flat-plate collectors as roof and three sides which received all the solar radiation incident on them. The roof and one of the sides face the south direction but the other sides face the south-east and south-west directions, repectively. The three sides tilted the horizontal plane to 30 degrees while the roof tilted to 15 degrees. The total surface area of the collectors is about of 1.68 m(2) and the capacity of the water storage tank is about 150 litres. The absorber consists of copper tubes formed in a serpentine shape which are connected to the tank by;two openings (inlet and outlet). A regulator is connected to the piping line to control the hot water consumption and the reverse flow after sunset. The thermal analysis of the liquid flat-plate collector and the performance of the solar water heater are derived based on the steady state analysis. A comparison between the compact unit and another type which has an elevated tank is done. The results show that the proposed salar water heater gives good performance and can provide a quantity of hot water of about 175 litres/day at an average temperature range from 40 degrees-60 degrees C depending on the weathering conditions and solar intensity.