PERFORMANCE ASSESSMENT OF PARABOLIC TROUGH SOLAR COLLECTORS

Abstract

In this study, a detailed parametric study of a solar parabolic trough collector is presented. The current condition of our environment compels us to restrain our use of fossil resources for energy production. It is our immediate priority to shift to renewable sources of energy which are non polluting and can be replenished in a short amount of time. Solar energy is a feasible option before us to fulfill our energy requirements. Concentrating solar collectors make use of the solar irradiation falling over the surface of the Earth. The high concentration ratios of collectors have the potential to transform the solar insolation into high heat energy. This energy may be used for a number of purposes like power production, process heating, refrigeration and many more. Parabolic trough solar collectors are widely used all over the globe as they can produce temperatures as high as 300°C. They are a type of line focusing solar collectors equipped with sun tracking mechanism. In this project, a mathematical model is formulated in EES of a parabolic trough solar collector and various parameters of it are calculated from the input conditions. The parameters like temperature of receiver, collector heat removal factor, overall loss coefficient, thermal efficiency of collector and optical efficiency are calculated and plotted in the form of a curve. This parametric calculation is carried out for every month of the year at different time intervals and all the values are tabulated and presented in the form of a curve. It is inferred from the calculations that the maximum thermal efficiency is obtained for the month of May which is 59.57%. Also, the properties are modeled at different mass flow rate of thermic fluid at different time of the day to get a fair idea about how the output characteristics vary with the variation in input v parameters. Three values of mass flow rate are used in this study that are 0.0986 kg/s, 0.0886 kg/s and 0.0786 kg/s and the corresponding variation in properties is presented in the form of a curve. It is also observed that the efficiency of the collector increases if the flow rate of heat transfer fluid is increased. However, the fluid exit temperature increases with the decrease in mass flow rate of heat transfer fluid.