A secondary reflector geometry optimization of a Fresnel type solar concentrator

The present paper aims to develop a new shape of secondary reflector for Fresnel linear concentrator; it rep-resents the continuation of a series of optimization carried out on a solar prototype with Fresnel type concen-tration, the new developed form represents a Double Parabolic Concentrator (DPC). This study was carried out through an optimization scheme in order to determine the parameters that influence on the prototype's per-formances. For this purpose, a numerical model is proposed. It aims at determining the different performance of the solar prototype. In this context, a parametric study and an optimization were carried out in order to determine the influence of certain parameters on the prototype's performances, namely: 1) the secondary reflector: Double Parabolic Concentrator (DPC), and 2) the different elements that characterize it such as the focal length, the aperture, the spacing, and the tube position. The modeling of the various parameters describing the solar field was carried out by the Monte Carlo ray-tracing (MCRT) method. The results are analyzed and presented in the form of tables and curves. In fact, they allowed the determination of the optimal configuration of the solar receiver. According to the optimization results, we can notice that the optimal DPC is not a double parabola. Moreover, the new form of DPC has a power gain of 10 to 13% compared to the existing form and also gives an optical efficiency of the receiver which reaches 100 %, that means that all the rays which cross the glass are absorbed by the tube. As a result, this configuration gives better theoretical and experimental performance. On the basis of this optimal configuration, several thermal power stations based on LFR technology have been produced and marketed.

Automated summary

This paper aims to develop a new shape of secondary reflector for Fresnel linear concentrator. Through parameter optimization, the optimal configuration of the secondary reflector and other elements has been determined, improving the efficiency of light utilization and energy collection.