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 incidént 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° while the roof tilted to 15°. The total surface area of the collectors is about of 1·68 m2 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 solar 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°—60°C depending on the weathering conditions and solar intensity.
KeywordsCompact unit-liquid flat-plate collector solar energy thermal analysis water heating
Unable to display preview. Download preview PDF.
- 1.Ken Baynes 1976‘About’ Design (London: Design Council Publication, Hazell Watson & Viney Ltd)Google Scholar
- 3.Lu Wei De and Guo H T 1984 ‘Performance of a gravity assisted heat pipe solar collector’Int. J. Solar Energy 3 1Google Scholar
- 4.Metweally A N, 1990 ‘Design and performance of an extended compact-tunnel solar integrated air dryer’ Proc. Second Int. Conf. on Renewable Energy, Cairo, Egypt 233Google Scholar
- 5.El-Haggar S M, El-Assy A and Ghanem I M 1994Assessment of novel flat-plate solar collectors compared to the conventional design’, Proc. Fourth Int. Conf. on Energy Development and Environment, Cairo, Egypt 37Google Scholar
- 6.El-Haggar S M, El-Assy A and Ghanem I M 1994‘Temperature distribution in flat-plate solar collectors using finite element technique’, Proc. Fourth Int. Conf. on Energy Development and Environment, Cairo, Egypt 9Google Scholar
- 7.Zerrouki A 1993‘Determination of the long term thermal performance of natural circulation solar energy water heater, Third Int. Conf. on Renewable Energy Sources, Cairo, Egypt 307Google Scholar
- 9.Felske J D 1979‘Analysis of an evaluated cylindrical solar collector’ Technical Note, Solar Energy p. 22Google Scholar
- 11.Badr N M 1982 ‘Theoretical and experimental study of photovoltaic system performance’, MSc thesis Cairo University, EgyptGoogle Scholar