DESIGN, IMPLEMENTATION AND PERFORMANCE TESTING OF A NOVEL SOLAR COLLECTOR

The aim of this work is to design, construct and evaluate the performance of a solar water heater system called a novel solar collector system [2] with an experimental and mathematical calculation, where the behavior of the collector is mathematically presented. The new type of the solar water heating system differs from the other conventional systems by integrating the collector and the storage tank into one piece of equipment, which can be considered as self-contained unit, acting as a solar collector and a storage tank at the same time. The experimental part of this work included the measuring of the pipes surface temperature, inlet water temperature, outlet water temperature, glass temperature and ambient temperature under given flow rates. In the theoretical part, outlet water temperature, pipes surface temperature, useful energy and the amount of solar radiation incident were calculated by applying the governing equation and were compared with measured data. It has been found from the assumption of one dimensional heat flow that some deviation occurs between the experimental investigation and numerical results of collector mean plate temperature due to the systematic and instrumentations errors in temperature measurements and the assumption of no temperature gradient around the tubes. It was found for the constructed system that the value of the overall heat loss coefficient was about 7.5 W/m2. °C (average value) and it is accepted when compared with the literature, also the values of heat removal factor are found in the range 0.86-0.88 and the collector efficiency factor  

value about 0.98 as a mean value. The instantaneous collector efficiency was found to be about 0.8-0.86, which is larger than that for the conventional system. The comparison of the predicted temperature difference across the collector and the efficiency of the system showed a good agreement with the experimental results.