The Research On Wind Effect Of Solar Energy Utilization Structure

Heliostats and trough concentrators are concentrating devices of solar thermal power generation systems.As a random load,the wind load is the main factor that affects the efficiency and safety of the condenser.Therefore,the research on wind resistance of heliostats and trough concentrators is of great significance.By applying the wind-break wall to the wind-proof design of the heliostat,the optimal parameters of the wind-break wall can be obtained to improve the wind-induced effect of the heliostat.The structure of trough condenser is large in the amount of steel and high in cost,and the optimization of the steel quantity can reduce the cost effectively.It is helpful to analyze the concentrating efficiency of the condenser by studying the mirror deformation of trough condenser under wind load and giving the analytic solution of the mirror deformation.Based on above,the following research work is carried out in this paper:Firstly,the static analysis of the heliostat structure is studied.According to the pressure test data tested by wind tunnel,the equivalent static wind load of heliostat is calculated.Then establish the finite element model of heliostat in Midas,and carry out the static analysis under self-weight and wind load to obtain the deformation and combined stress at different elevation angles.The results show that the heliostat structure can work safely and the results of the deformation calculation in normal service condition can be used to study the condenser efficiency of heliostats.Secondly,the influence of the wind-break wall on the peak wind pressure coefficient of the typical measuring points is studied.When there is a wind-break wall,the interference factor of the peak pressure coefficient of the typical measuring points in the most disadvantage wind direction is analyzed,and the optimal height,the optimal porosity and the best distance between the wind-break wall and the heliostat are determined.When the height of the wall is 0.8H,the porosity is 40%,and the distance from the heliostat is 6h,the wind-break wall works best on the peak wind pressure coefficient of the typical measuring points.Then,the influence of wind-break wall on the wind coefficient of the heliostat structure is studied.Taking the porosity,the distance between the wind-break wall and the heliostat as the design parameters,considering the obstruction efficiency of the wind-break wall as the objective function,uniform design method is used to arrange the experiment.Then the regression model between the average resistance coefficient,the average lift coefficient,the average torque coefficient and the parameters are established to optimize the wind-break wall parameters.The results show that the uniform design method can be used to optimize the wind-break wall,and the whole optimization process is simple and the result is reliable.Thirdly,in order to reduce the amount of steel used in the structure of the trough concentrator,taking the wing’s rod sizes,triangular truss’s rod sizes and the initial tension of cable as the optimization parameters,and considering displacement and stress as the constraint conditions,uniform design method is used to optimize the structure of the condenser in the most disadvantage conditions.The results show that uniform design method can be used to optimize the structure of condenser,and the steel quantity of condenser is saved by 10.3%under the control conditions of structural deformation.Finally,the deformation of mirror panel of the trough concentrator under wind load is calculated.The analytical solution of the mirror panel deformation of the trough concentrator is calculated based on the Levy solution in the plate and shell mechanics.The results show that the accuracy of the method can meet the engineering requirement.According to the analytical solution,the deformation of the mirror panel causes the reflected light to deviate from the focus.