AbstractThis paper describes an experimental study of a parabolic trough collector (PTC). The objective of the paper is to perform parametric investigations of the effects of flow rate and absorber water inlet temperature on the collector’s thermal efficiency for different levels of solar insolation under the climatic conditions of Silchar, Assam, India. The analysis was carried out over a year’s period covering different seasons. The optimum values of these input parameters for various solar insolation levels are also found out. It was shown that the effect of the mass flow rate is more significant than the absorber water inlet temperature as the collector thermal efficiency at the optimum mass flow rate is greater than that at the optimum water inlet temperature. And it happens at low solar insolation rates such as 552 W/m2. However, the highest thermal efficiency of the present collector is 65%, obtained when optimum values of input parameters are applied simultaneously. The present study provides insight as to the selection of these operating parameters for PTC-based solar water heaters in a low radiation zone like Silchar, Assam, India.
Keywords: Climatic conditions, Optimum mass, Solar insolation, Silchar, Water inlet temperature.