Simulation Study On Wind Load And Dust Accumulation Of Photovoltaic Panels Under Wind-blown Sand Environment

The fossil energy is facing a risk of depletion,and the environmental pollution is becoming more and more serious,searching new green energy has become a global consensus.Solar photovoltaic power generation has some advantages which don't exist in the traditional energy,so it has been widely concerned and obtained rapid development.Desertification zone is an advantageous area to develop large-scale photovoltaic power station,but dust deposition and erosion in the wind-blown sand environment have some seriously impact on the safely operate and the power prediction of photovoltaic power station.However,some references have reported lots of interesting results,there are still many deficiencies in the research of related scientific issues.Therefore,in this paper,the flow structure around the photovoltaic panel and the dust deposition and erosion law on the photovoltaic panel were simulated and analyzed by means of the fluid dynamics simulation method.Main research contents and results are as follows:Firstly,based on the DPM model,the flow structure around the photovoltaic panel under different installation angles is analyzed while the wind speed and particle size are fixed,and the amplification effect of inclined photovoltaic panels on the velocity of inflow wind is discussed.Through these simulated results the following conclusions are concluded,(1)the wind pressure coefficient of the photovoltaic panel in wind-blown sand is higher than the one under the net wind condition,and the wind pressure coefficient changes significantly with the change of the installation angle of the photovoltaic panel,and the pressure center gradually changes up to the center of the board surface;(2)with the increase of the installation angle of the photovoltaic panel,the erosion area of the dust particles on the photovoltaic panel is gradually increased,and ultimately dispersed in the entire surface of photovoltaic panel,and both the maximum erosion rate and the total erosion rate are approximately exponentially increasing.Secondly,variation rules of dust deposition rate on the photovoltaic panel under different conditions are discussed.The results showed,(1)the distribution of dust deposited on the inclined photovoltaic panel is not uniform under different wind speed and dust volume concentration in air.The stratification phenomenon appears along the panel's surface,which means that under the influence of dust deposition,the power generation efficiency of each grid photovoltaic module will be different,which will inevitably lead to some large hot spots on the photovoltaic panels;(2)when the inclination angle of photovoltaic plate and the incoming wind speed are fixed,the sand&dust deposition increases exponentially with the increasing of the particle size in the air.When the particle size and the inclination angle are fixed,the sediment on the photovoltaic plate increases with the increasing of the wind speed.(3)the amount of dust sediment on the photovoltaic panel increases gradually with the increasing of the volume fraction of dust particles in the incoming wind,and it firstly increases and then decreases as the dip angle of the photovoltaic panel increasing.It will reach the maximum value when the inclination angle is 35°;(4)the dip angle of the photovoltaic panel will affect the position where the maximum deposition amount is located,and it located at the upper part of the plate when the dip angle is less than 30 degrees,but it gradually moved upward from the lower part of the plate with the increasing of dip angle.(5)with the increasing of the dust deposition amount and the particle diameter,the light transmittance of the dusty glass plate became smaller.Finally,based on the light transmissivity model of dusty panels and the above simulation works,the influence of dust accumulation on the photovoltaic cells is discussed.The results showed that with the increasing of dust deposition,the effect of sediment on the transmittance of photovoltaic cells is more significant,and when the dust content on the photovoltaic panel is constant,the larger the sediment particle size,the better the transmittance of the photovoltaic glass.The above research results can provide theoretical and design basis for the safe operation of photovoltaic power station,and the dust removal technology of photovoltaic panels.