| The construction of photovoltaic power station in Gobi area,on the one hand,it can use solar energy to adjust the surface heat balance;on the other hand,it can play a wind barrier effect,inhibit soil wind erosion and evaporation,improve soil and crop growth environment,which is of great significance to the efficient use of local water and soil resources.Installation angle,array distance and array angle are the main layout parameters that determine the form of PV array,and play a decisive role in its wind load capacity and wind-proof effect.In view of this,based on computational fluid dynamics(CFD)and the flying-geese model,this paper studies wind force and speed of the herringbone PV array composed of five row panels under five array angles(30°,40°,45°,50°,60°),five installation angles(30°,40°,45°,50°,60°)and five array distances(1.5m,1.75 m,2m,2.25 m,2.5m)in line with the distribution characteristics of wind force and wind speed,the optimal condition is obtained finally.The main research contents are as follows:(1)In order to verify the reliability of the numerical model,the wind pressure and wind speed of a single PV panel are simulated and verified by wind tunnel experiments.The results show that: the wind pressure reaches the maximum at the middle point of the front edge of the panel,and gradually decreases at the right angle of the back edge,and the average determination coefficient of the simulated and measured values of the wind pressure at the monitoring point reaches 0.9996;the wind speed changes most significantly near the PV panel,and the simulation accuracy is characterized by “center height of PV panel”>“installation height of PV panel”>“1/2 installation height of PV panel”>“height of PV panel trailing edge”>“1.2m height”.It shows that the numerical model can simulate the distribution of wind pressure and wind speed.(2)The wind pressure distribution characteristics of herringbone PV array panels with different layout parameters are analyzed by using the partition counting statistics and classical statistics methods.The results show that: the distribution of array wind pressure is non-uniform,the average wind pressure decreases with the increase of row number,and the reduction is the largest in the second row;the proportion of monitoring points in the maximum wind pressure range(60～80Pa)is smaller than that in other wind pressure ranges,and they are all located on the outer airfoil line of the array.With the increase of array angle,the average wind pressure first increases and then decreases;with different installation angles,the average wind pressure is 60°>45°>50°>40°>30°;with the increase of array spacing,the average wind pressure first decreases and then increases,and reaches the peak at 1.5m.In order to provide theoretical guidance for local strength optimization of herringbone PV array.(3)With the help of wind pressure carrying coefficient and variation coefficient,the wind load capacity of herringbone PV array is expressed,and the response law of its wind load capacity to layout parameters is discussed,and the reasonable parameter range is obtained.The results show that: in the actual construction of the herringbone PV array composed of this type of PV panels,the array angle should be no more than45°,the installation angle should between 30°and 50°,and the array spacing should be1.75～2.5m.In order to provide a scientific basis for the optimal layout of wind load capacity of herringbone PV array.(4)The distribution characteristics of wind speed in computing domain of herringbone PV array with different layout parameters are analyzed by using classical and spatial statistical methods.The results show that: under different array angles,installation angles and array spacing,on the one hand,the response of average wind speed at characteristic height to layout parameters presents a certain rule,with different array angles as 30°>45°>50°>40°>60°;with the increase of installation angles,the response below "installation height of PV panel" decreases gradually,while the response above "center height of PV panel" is 50°>30°>40°>45°;the response of different array spacing is 2.5m>2.25m>1.75m>2m.On the other hand,the average coefficient of determination of the parameters fitting of the semi variance function model of the characteristic height wind speed is 0.953,0.949 and 0.883 respectively,and the Moran’s I is close to 1,which indicates that the wind speed measuring points are arranged reasonably,the distribution fitting is good,and the spatial correlation is strong.In order to provide a simple method for wind speed prediction and measurement in the computational domain of herringbone PV array.(5)On the basis of optimizing the wind load capacity of the array,the response law of the wind protection effect to the layout parameters is analyzed,and the optimal parameter combination is obtained.The results show that when the array angle is 40°,the installation angle is 45° and the array spacing is 2m,the array both has good wind load capacity and wind protection effect.In order to provide a scientific reference for the optimal layout of wind protection effect of herringbone PV array. |
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