Numerical Research Of Aerodynamic Characteristics Of Wind Turbine Blades

With the intensification of energy and environment problems,wind energy as a green energy is attracting more and more attention,wind power generation is currently the main application of wind power,so it is of great significance to study the aerodynamic characteristics of wind turbines.In this paper,a numerical scheme was applied to study the aerodynamic characteristics of wind turbine blades under different Reynolds number,angle of attach,icing form and rotation state.Firstly,the aerodynamic characteristics of 2D airfoils was simulated and analyzed.the effect of different turbulence models such as Realize k-ε turbulence model,SST k-ω turbulence model and Spalart-Allmaras turbulence model and different near-wall treatment methods were studied under different angle of attach.By comparison with experimental results,it was found that Realize k-ε turbulence model combined with the standard wall function can well simulate the aerodynamic characteristics of airfoils,and it can predict the occurrence of flow separation accurately,however,the SST k-ω turbulence model and the Spalart-Allmaras turbulence model have a deviation from the prediction of flow separation at high angles of attack.Secondly,based on the 2D airfoils numerical simulation,the Realize k-ε turbulence model combined with the standard wall function was used to simulate and analyze the influence of icing on the aerodynamic characteristics of the 2D airfoils,the influence of glaze ice and rime ice on the aerodynamic characteristics of the 2D airfoils was compared,it was found that rime ice has little influence on the aerodynamic characteristics of the 2D airfoils,however,the aerodynamic characteristics of the 2D airfoils was seriously deteriorated by glaze ice,the lift coefficients of airfoils are greatly reduced and negative drag coefficient occured when the angle of attack is small.Considering the three-dimensional effect of flow,we can not fully grasp the three-dimensional aerodynamic characteristics of blades through two-dimensional simulation of airfoils.Then,the aerodynamic characteristics of 3D blade are simulated and analyzed under different Reynolds number,the simulation results of Realize k-ε turbulence model and SST k-ω turbulence model with their corresponding wall function were compared,it was found that Realize k-ε turbulence model combined with the standard wall function is better.The three-dimensional effect of the blade is analyzed by comparing with the two-dimensional simulation.Finally,by the simulation of the passive rotation of the wind turbine blades,the changes of blades rotation speed and the corresponding aerodynamic force of the blades were analyzed when the wind turbine is in the uncontrolled state or when the fault occurs.