Novel additive-manufactured tracking solar concentrating system for cooking applications: Design, geometry assessment, and optical evaluation

Abstract

[eng] A novel solar concentrating system for cooking applications was developed, featuring a stationary reflector and a flat heliostat with equatorial tracking. This design allows for simple one-axis tracking at a constant speed with no need for deformable reflectors, ensuring the direction of the concentrated radiation in the cooking area remains steady and a quasi-constant power capture regardless of the Sun's position. The concentrator is made from 3D printed flat tiles, allowing for an easy do-it-yourself manufacturing process and avoiding highly focused irradiance on the receiver. The geometry of the reflector was scanned and compared to an ideal CAD reflector model, revealing some assembly imperfections, and a slightly concave tile geometry which causes a moderately sharp concentration peak. The irradiance distribution on a plane target near the effective focus of the reflector was analysed with a photographic flux mapping technique, and the results were compared to those obtained from ray tracing simulations of the ideal CAD model, confirming the tile concavity predicted by the geometrical examination. Conversely, it shows a reduction in the total energy gathered on the entire target plate when compared with ray tracing outcomes.