An Experimental Investigation of the Efficiency of A Stationary Helical Solar Water Heater

Due to increasing demand for energy and rising cost of fossil fuels, solar energy is considered an attractive source of green energy that can be used to heat water in domestic and industrial sectors. Solar water heating systems generally consist of a solar radiation collector, working fluid, a storage tank, a pump, a piping unit and an auxiliary heating unit1,2. The most important factor in solar water heating is its efficiency. The efficiency of a solar water heating system is based on the proportion of useful energy that is received from the heated water to solar irradiance5,6. Solar collectors’ properties play the main role in the efficiency of solar water heating systems7. Scientists and engineers have been Abstract The shape and geometry of a solar collector is an important factor in solar-to-thermal energy conversion. In this paper, a new stationary solar collector called helical solar collector was designed and investigated. The performance of this collector was experimentally studied using ASHRAE standard. Experiments were performed with water as a working fluid in the outdoor condition of Ahwaz, a city in the south of Iran. The findings indicate that the average of its thermal efficiency is about 53%, and that it can be used as an efficient new water heater. The experiments show that the efficiency of the helical solar water heater increases through adding the mass flow rate. Article History