INVESTIGATION OF TEMPERATURE DISTRIBUTION AND HEAT TRANSFER MECHANISM IN COLLECTOR-CUM-STORAGE SOLAR WATER HEATER

Abstract

The perforinance of integral collector-cum-storage solar water heater depends upon the aperture area of the collector, intensity of solar radiation, inlet temperature of the water being supplied. There is no well-established rational design procedure for collector-cum-storage solar water heater. It is therefore essential that efforts should be made to establish relationship between inlet temperature, area of the collector and depth of the storage tank. Due to this performance of the system cannot be predicted rationally. It was therefore proposed to design and fabricate an experimental set-up to collect data of temperature of collector surface, across the depth of the absorber-cum-storage tank at mid section and bottom surface. The data have been processed and presented in the form of plots of collector efficiency, temperature distribution graphs for the mid section and top surface of absorber-cum-storage water heater, and heat storage efficiency of hot water during the night and performance plot. From the performance plot it is evident that the system's average thermal efficiency decreases with increase in temperature rise parameter. This also confirms the theory that higher inlet temperature leads_to higher absorber plate temperature and hence higher losses thus reducing the collection efficiency. On the other hand heat storage efficiency during the night increases with ticreasing in inlet temperature.