Flux concentration on tubular receiver of compound parabolic collector by surface areal irradiance method of ray tracing

Abstract

Ray tracing for solar collectors finds wide application for designing the components. In this research, a solar flux concentration on the tubular receiver of compound parabolic collector (CPC) is determined by a novel approach of surface areal irradiance (SAI). The objective of this method is to determine the solar reflected irradiance at the receiver by incorporating effective areas of reflector and receiver. These areas are determined by 2D graphical ray tracing technique. Multiple ray tracing iterations are performed on various geometric possibilities of receiver–collector combinations by varying receiver diameter and height. The collector dimensions are fixed as per authors previously designed CPC to reduce the number of possibilities of receiver – collector combinations. The results of these iterations are presented in terms of utilization ratio (U), projection ratio (P) etc. based on which concentrated solar flux and heat equations are determined. It is observed that there is saturation point for all receiver diameters at which a receiver – collector combination gives highest utilization ratio and the corresponding height gives the best location for that receiver. SAI method gives a strong methodology for designing solar collectors on the basis of utilization ratios and heat equations.