Study on Dust Deposition Mechanics on Solar Mirrors in a Solar Power Plant

Abstract

Solar energy is considered to be one of most promising renewable energy sources because of its availability and cleanliness. The phenomenon of dust deposition on solar mirrors greatly reduces the power generation of solar power plants. In this work, the motion behaviors and deposition mechanics of dust particles are analyzed by the discrete element method (DEM). The effects of environmental and solar mirror conditions and particle self-factors on dust deposition weight are systematically studied here. The research results show that dust particles, after particle collision, immediately adhere to the mirror or rebound and finally flow away from the mirror, or they otherwise may remain stationary after making some relative motion. Alternatively, they may glide for some distance and finally come to rest on the mirror or leave from the system. Different motion behaviors after particle collision depend on different leading forces. Here, the leading forces are the liquid bridge force (Fc) and the contact force (Fb). When the leading forces are Fc, or Fc, and Fb, the dust particles will be deposited on the solar mirror. Besides, the force Fc cannot be negligible when studying the motion processes of dust particles. The dust deposition weight on solar mirrors can be controlled by altering the environmental and solar mirror conditions, and particle self-factors. In essence, dust deposition weight on solar mirrors decreases when decreasing the leading force Fc or increasing the leading force Fb. The research results give theoretical guidance for the prevention and removal of dust deposition on solar mirrors.