| To improve aerodynamic performance of wind turbine blade profiles is the key to increase the efficiency of wind turbine and to develop industry of wind energy. Some results of research on increasing aerodynamic performance of wind turbine are presented in this paper, which include the research of tailored airfoils for wind turbine rotor blade and the research of lift coefficient improvement and stall deferring of airfoils by stationary air suction and oscillating jet.Numerical simulations of flow around 7 profiles with large range attack angles are made. Finite volume method, SIMPLE method and k-ω based SST turbulence model are used. Some results of simulations have contrasted to the experiment results and show high reliability. Through these simulations, the aerodynamic performances of these profiles are obtained. The results indicate that tailored profiles of wind turbine have better aerodynamic performances than traditional profiles. The results also show that profiles from deferent part of wind blade have deferent aerodynamic performances. Influence of aerodynamic performances by geometry parameters of profiles is summarized through analyses. Numerical simulations and wind tunnel experiments of flow around NACA0015 airfoil by adding stationary air suction and oscillating jet at the head part of the airfoil are made. Results indicate that the stationary air suction and oscillating jet can improve the aerodynamic performance and defer the stall. Stationary air suction pumps out lower energy fluid near the suction surface of the airfoil and makes main stream close to the surface. It results lift improvement and drag decrease. Turbulence of oscillating jet forms a forced eddy at the suction surface of the airfoil and forced it break off from the surface at the same frequency of the oscillating jet. This increases kinetic energy of fluid near the suction surface and the lift of the airfoil. The best location, optimized momentum coefficient of the stationary air suction and oscillating jet, the optimized dimensionless frequency of the oscillating jet is obtained. |
