Paper Title
Effect Of Inclination Angle On Solar Radiation Of Water-In-Glass Evacuated Tubes Of Domestic Water Heater

The water-in-glass evacuated tube is an integral part of evacuated tube solar water heater. The water-in-glass collector is the mostly used form of evacuated tube collector because it has higher thermal efficiency than metal-in-glass tubes and has simple construction requirements and hence lowers manufacturing cost. Solar water heaters with evacuated tube collectors perform better than that of flat plate collector. Borosilicate glass is used for water-in-glass evacuated tube. The vacuum gap is made between inner tube (diameter 47mm) and outer tube (diameter 58mm, length 1800mm). Inner glass tube is coated with aluminum oxide to absorb more heat. Water heating systems are provided by solar energy (sunlight) directly to thermal energy. This system was tested in Mandalay Technological University and used 6 numbers of evacuated tubes are mounted with different tilt tube angles. Performance test is made during 8-hours of daytime in real use. This paper discusses the experimental and theoretical study conducted on evacuated tube collectors mounted at different angles of inclination. It is found that experimental results give a good agreement with the theoretical result. In this paper, the utilization of solar energy through solar water heating systems plays a big role in the quantity of conventional energy required. Index Terms—Water-in-Glass Evacuated Tube, Solar Water Heater, Solar Radiation, Angle of Inclination,