Effects of receiver parameters on the optical efficiency of a fixed linear-focus Fresnel lens solar system with sliding adjustment

Abstract

To effectively eliminate optical end loss for small-scale linear solar concentrators, a fixed linear-focus Fresnel lens solar system (FLFS) with triangle cavity receiver is described and the principle is provided. The effects of the receiver parameters including receiver position f, solar declination angle δ, solar hour angle ω, internal surface absorptivity αaband end plane reflectivity ρron the end loss ratio (μoel) and relative optical efficiency (ηre−opt) of the proposed system have been studied by the control variable method and Monte Carlo ray tracing (MCRT) method which is implemented by software TracePro®. Significance tests of critical factors are conducted to assess the effect of receiver parameters. These results revealed that the FLFS could effectively solve the problem of optical end loss of linear solar concentrators. When f=650mm and δ= 0°, 8°, 16°, and 23°27′, the corresponding average ηre−optat ω from 0° to 60° are 0.9459, 0.9422, 0.9145, and 0.8144, respectively. As δ increases, reducing f can ensure the system operates at a high-efficiency state. The ηre−optshows a positive relationship with αaband no relationship with ρr. δ occupies the greatest significant influence on ηre−opt, which is followed by ω, αaband f.

Keywords

• Solar concentrator
• Triangle cavity receiver
• Linear fresnel lens
• Fixed linear-focus
• Optical efficiency