Study On Dust Deposition Characteristics And Dust Removal Mechanism Of Trough Solar System Based On Regional Climate

The parabolic trough solar thermal power generation system is a widely used technology in the field of solar thermal power generation.However,since solar thermal power plants are commonly located in windy and sandy regions of northwest China,dust accumulation on the concentrator surface has become a major issue that significantly affects the system’s performance.The presence of dust particles in the mirror causes light absorption and scattering,leading to a decrease in the system’s power generation capacity.Therefore,understanding the deposition characteristics of dust on the mirror surface and its impact on concentrating performance based on regional characteristics is crucial for engineering practical applications.This study examines the full life cycle of dust particles,including sedimentation,accumulation,and detachment,through experiments and simulations based on typical climatic factors in the region,providing a systematic and scientific theoretical foundation for optimizing dust removal strategies and improving concentrating performance.Firstly,the physical properties of the dust particles in the region are analyzed in detail through microscopic analysis using a scanning electron microscope（JCM600）and energy dispersive spectroscopy（EDS）.Based on this,typical rainfall working conditions in the area are selected for experimental research on the relationship between rainfall and atmospheric particle concentration.The results show that the shape of the dust particles accumulated on the concentrator mirror is mostly spherical,and the main component is Si O₂.Rainfall can effectively remove the particles in the air and deposit them on the ground.When the daily precipitation amount is between 10-25mm,the removal rate of particle concentration is as high as 83.33%.Secondly,the adhesive mechanics model of the dust particles is analyzed,and extensive experimental testing is conducted to reveal the distribution characteristics and removal patterns of mirror dust under natural environmental factors.Based on this,the concentration efficiency is quantified as an indicator,and optical simulation software based on the Monte Carlo tracing method is used to further explore the impact of various working conditions on the system’s optical performance output.The results show that rainfall is the most influential climatic factor.When the precipitation is less than 4.1mm,it can cause mirror pollution,but as the precipitation increases,the rainfall can form runoff and wash the mirror,resulting in a good cleaning effect.The optimal concentration efficiency of the collector under the action of rainfall is 0.382,which is the highest compared to other climatic factors,indicating that rainfall has the largest influence.Finally,the forced removal of mirror dust using compressed air and rainfall is studied.Experimental methods are used to investigate the optimal working conditions for mirror surface dust removal using compressed air,as well as the combined removal of dust using compressed air and rainfall.The weights of the factors involved in the combined removal process are studied using an orthogonal test.The results show that the highest removal efficiency for mirror dust using compressed air is achieved at an output pressure of 0.6 MPa and a mirror tilt angle of 60°,with a maximum efficiency of 0.758.The optimal output pressure for mirror dust removal after moderate rainfall is0.4 MPa,with an average cleaning rate of 0.07.The weight order of the factors affecting the removal efficiency of mirror dust in the combined cleaning process is rainfall>output pressure>nozzle tilt angle,with the most efficient combination being rainfall of 18.4 mm,output pressure of 0.6 MPa,and a nozzle tilt angle of 67°.