Numerical Investigation of Optical Performance in V-Trough Solar Concentrators Using Bifacial and Trifacial Absorbers With Various Bottom Reflector Geometries

Abstract

Abstract. The present study investigates the optical performance of a V-trough solar concentrator using four distinct bottom reflector configurations: flat, parabolic (PP), circular (CC), and a combination of circular and parabolic (CC–PP). Detailed ray tracing simulations were conducted to analyze the distribution of heat flux, optical efficiency, and local concentration ratio (LCR) across varying incidence angles for each configuration. The analysis compares bifacial and trifacial absorbers using tonatiuh ray tracing software. The novel trifacial absorber features three active surfaces arranged in a triangular layout, which enhances the light capture and optical efficiency. The left and right lateral surfaces of the trifacial absorber exhibit better uniformity and local concentration ratio across all incident angles. The trifacial system outperformed the bifacial system with all types of reflector configurations (flat, CC, PP, and CC–PP). The CC–PP achieved the maximum optical efficiency of 85%, 66%, and 40% (trifacial) and 46%, 53%, and 38% (bifacial) at incident angles of 0 deg, 20 deg, and 40 deg, respectively, followed by PP, CC, and flat configurations. The same trend follows with other incidence angles. Among all bottom reflector configurations, the CC–PP exhibited better performance, reaching a peak value of local concentration ratio of 4.5 at 30 deg and a maximum heat flux of 4500 W/m2 on the bottom surface.