Optimization of Coupler inlet for Planar Solar Concentrator

• Main Authors: Tien-Hsiang Yu, Tun-Chien Teng
• Format: Article
• Language: English
• Published: Taiwan Association of Engineering and Technology Innovation 2016-08-01
• Series: Proceedings of Engineering and Technology Innovation
• Online Access: http://ojs.imeti.org/index.php/PETI/article/view/232

In this study, we implemented optimization for the coupler inlets of the planar solar concentrator, which was proposed in our prior work. The planar solar concentrator had a waveguide slab to carry an array of light-collecting elements thereon. The light entering the elements is focused on the coupler inlets and guided into the slab with propagating therein through total internal reflection (TIR). Thus, all the light from the elements is guided to the ends of the slab and highly concentrated. Because the coupler inlets couple light into the slab and also decouple the light propagating in the slab in subsequent interactions, they must be optimized to balance between coupling efficiency and decoupling loss. The optimized arrangements of coupler inlets included three types here: uniform-thickness platform, stepped-thickness platform, and stepped-width platform. In the simulation, the three types have the same area of the inlet to keep the concentrator with the same tolerance of the incident angle of light. We analyzed both the optical efficiency and range of the vertical angular distribution of the light reaching the outlet end of the slab; then made a comparison for the three inlet arrangements. The simulation results demonstrate the stepped-thickness and stepped-width platforms provide higher efficiency and concentrated irradiance.