Fabrication and Performance Evaluation of Rectangular and Circular Cross Section Solar Water Heaters.

Abstract

Solar energy is getting popular nowadays. Technologies have been developed which made solar energy a cheaper and reliable source of energy. Due to pollution and other factors, solar has become the most popular source of energy. Along with power generation, now water heaters are also developed which are working on the solar technology. It is a reliable method and can be used in areas which do not have access to wood, coal and gas. This project is based on design and fabrication of solar water heater. The main focus is given on increasing surface area exposed to sunlight. In this project, active water heaters are employed with pipes of circular and rectangular cross section. Local materials and manufacturing methods were used to fabricate the solar water heater to limit the cost of project. The result obtained was compared for both the configurations. The temperature rise was not remarkable as was expected. Two distinct problems were observed regarding this. One was the pipes were not run full of water; as a result heat on pipe surface couldn’t transfer the heat properly to the flowing water. There was always a gap between the hot surface and top layer of water in the pipe. Secondly, the diameter/ width of pipes were large; as a result heat was transferred to the upper level of water only.