Optical and thermal performance enhancement of parabolic dish collector: Effects of cavity receiver's surface modification and covering aperture

Abstract

Regarding the increasing demand for renewable energy sources, especially solar energy, researchers are trying to develop more efficient solar energy systems. Parabolic dish collectors are solar thermal collectors that can be utilized in various thermal energy system applications. Cavity receivers of the dish collectors are one of the crucial parts of these collectors, and the studies on their thermal performance improvement and heat loss reduction are critical. The current study follows the experimental investigation of the glass covering of cylindrical-conical cavity receiver along with the cavity's coil surface modification with various geometries. According to the results, applying the glass covering enhanced the thermal efficiency by 18.42%, with a maximum thermal efficiency of 52.61% and optical efficiency of 57.89%. Rectangular-triangular geometry for the surface modification of the cavity's coil resulted in a maximum optical efficiency of 59.17%. Overall, rectangular geometry had the best thermal and optical efficiency enhancement results.