Energy and Exergy Analysis of Wavy Finned Absorber Solar Air Heater

Abstract

This paper deals with the analytical investigation on the energy and exergy analysis of wavy fin solar air heater. A mathematical model has been developed to evaluate the effect of various complex geometries of wavy fin such as fin spacing ratio, fin cross section aspect ratio and flow length ratio. The theoretical investigation showed that the exergy efficiency decreases with the increase in mass flow rate, increases, with the decrease in fin spacing ratio, flow cross section aspect ratio and flow length ratio. For the entire range of fin spacing ratio and cross sectional aspect ratio an optimum value of exergy efficiency has been found as 2.3% for the mass flow rate of 0.034kg/s-m² and corresponding rise in air temperature of 0.028K-m²/W. Also, the results obtained from theoretical analysis of wavy finned solar air heater have been compared with the available experimental results of rectangular finned, triangular finned as well as a plane solar air heater.