Modelling and Layout Optimization of Heliostat Field

The simulation model of the circular heliostat mirror field based on the Monte Carlo ray tracing method was studied, and the mirror field layout was optimized on this basis to obtain higher optical efficiency. Firstly, according to the spatial relationship between the heliostat and the collector, the mirror field coordinate system with the center of the bottom of the absorption tower as the origin is established, and the mirror coordinate system is established with the center of the heliostat as the origin. On this basis, the behavior of the heliostat under focused light was simulated. Secondly, the following important indicators are calculated: (1) Shadow occlusion efficiency: In this paper, a K-D tree is introduced to efficiently obtain heliostats that may cause occlusion, and then the occlusion matrix method is used to screen these heliostats, and finally the incident and outgoing rays are traced based on the idea of discrete ray tracing. (2) Truncation efficiency: In this paper, the Monte Carlo ray tracing method is used to calculate the ratio of the reflected light cone hitting the light collector. (3) Through the information of solar azimuth, local time, geographical factors and other factors, the necessary parameters such as cosine efficiency, atmospheric transmittance, etc., are further calculated. Finally, based on the radial grid layout commonly used in the industry, the mirror field layout was redesigned, and then the improved PSO algorithm was designed to solve the problem.