Determination of Concentrated Flux Intensity and Distribution for Solar Parabolic Trough Concentrator

The solar parabolic line focus collector can be used to generate high temperature thermal energy. The performance of the parabolic trough collector depends on the distribution of flux on the receiver surface. In this article, concentrated flux intensity and its distribution at the focus of a 15 m² parabolic trough collector is made of glass mirror with 2.5 m aperture and 65° rim angle is determined. The dispersion angle of the collector is calculated based on the image size as 0.27°. The analytical simulation is carried out to analyze the flux distribution at the focus, above and below the focus of the parabolic trough collector considering the sun limb darkening effect. The effect of rim angle on the flux distribution and concentration ratio of the collector is studied. The minimum image size has been observed at rim angle 45°. The image size varies linearly between the rim angles 20° to 70° and increases exponentially when the rim angle below 20° and above 70°. The results show that image size and flux distribution is not uniform at same distance from above and below the focal plane. Based on the flux distribution, the surface receiver has been developed to analyze the performance of the parabolic trough collector.