Journal of Physical Chemistry & Biophysics
Open Access

Abstract

Optimization Design of Heliostat Field Based on Monte Carlo and PSO Algorithms

Bin Zhao*, Xia Jiang and Yi Wu

Tower solar thermal power generation technology is a new low-carbon and environmentally friendly clean energy technology. In this paper, based on Monte Carlo algorithm model and Particle Swarm Optimization (PSO) algorithm, the optimization model of heliostat mirror field is constructed, which is of great practical significance for effectively improving the collection and conversion efficiency of solar energy and promoting the sustainable development of clean energy.

First of all, this paper first visualizes the coordinate data of each heliostat attached in the spatial coordinate system, and carries out preliminary screening and cleaning of the data. Then combined with the known conditions in the topic and the formula in the appendix to determine the shadow occlusion efficiency (η_sb), cosine efficiency (η_cos), atmospheric transmittance (η_at), collector truncation efficiency (η_trunc) and mirror reflectance (η_ref) and other 5 parameter values, these parameter values into the helioscope optical efficiency calculation formula, to solve the average optical efficiency on the 21^st of each month, Then the average optical efficiency of 12 months is calculated, and the average annual optical efficiency of heliostat field is 0.4512. Similarly, the average annual output thermal power of the heliostat field is calculated as 27.5713 MW by using the calculation formula of the output thermal power of the heliostat field, and then divide the annual average thermal power by the sum of the mirror areas of all heliostats in the whole field (there are 1745 heliostats, and the area of each mirror is 36 m²). Finally, the average annual output thermal power per unit mirror area is 0.4401 kw/m².

Second, this paper uses Monte Carlo direct model and PSO algorithm to build a mathematical model of optimization design of heliostat mirror field. The mirror height is not greater than the mirror width, the mirror side length is between 2 m-8 m, the installation height is between 2 m-6 m, the mirror will not be in contact with the ground when rotating around the horizontal axis, the distance between the base centres of the adjacent two mirrors must be at least 5 m more than the width of the mirror, the helioscope is not installed in the circular area of 100 m around the endothermic tower, and the radius of the helioscope field of the whole circle is 350 m, the size parameters of each helioscope and the installation height is the same, the rated annual average output thermal power of the heliostat field is not less than 60 MW as the constraint condition, the position coordinate of the absorption tower, the size of the heliostat, the installation height, the number of heliostat and the position of the heliostat are taken as the design parameters, and the maximization of the annual average output thermal power per unit mirror area is taken as the objective function. After entering the model, the optimal design parameters are solved as follows: The position coordinate of the absorption tower is (0, -200), the size of the heliostat is 3.5 m × 3.5 m, the installation height is 2 m, the total number of the heliostat is 8440, and the total area is 103390 m².

Finally, on the basis of step two, the helioscope installation area is divided into four ring areas. The helioscope in the same area has the same size and installation height, while the helioscope in different rings has different size and installation height, so as to effectively optimize the parameter values of truncation efficiency and shadow occlusion efficiency. The optimal design parameters in each ring can be obtained by using the established optimization model.

Published Date: 2023-11-02; Received Date: 2023-10-03