The Effect Of L Tip Vane On Aerodynamic Performance Of 5MW Horizontal Axis Wind Turbine

With the wind turbine towards the development of large-scale,improving wind energy exploitative efficiency of wind turbine and increasing the aerodynamic performance of the blades has become one of the key issues to be solved in the development of wind turbines.The tip vane is simple to install,which usually used to control the surface flow of the blade.In order to research the influence of the tip vane on the aerodynamic performance of the wind turbine,the artical takes the NREL 5MW wind turbine as the research object.L tip vane(tip vane on suction surface)was installed on the blade tip to study the influence of L tip vane on the aerodynamic performance of wind turbine in unyaw state and yaw state.The main contents and conclusions are as follows:1.The article studied the influence of the installation position of the tip vane for the wind turbine’s aerodynamic performance at rated wind speed by numerical simulation method and revealed the influence mechanism of V tip vane,L tip vane and tip vane of pressure surface on the wind turbine power and blade tip’s pressure.The results show that L tip vane plays a major role in increasing the output power of wind turbine and increasing the pressure differential between the upper and lower surface of blade tip.2.Changing the installation angle(15 °～85 °)and length(0.5 m～3 m)of the L tip vane under different wind speed,the influence of L tip vane on the wind turbine aerodynamic performance,the stress field,blade tip vortex and the load is studied by SST k-ω turbulence model.The results show that the installation of L tip vane on the blade tip reduced the downwash velocity around the blade tip,changed the distribution of tip circulation,reduced the intensity of tip vortex,supressed the premature separation of tip airflow and blade,increases the pressure differential between the upper and lower surfaces of the blade tip,enhenced the output power of the wind turbine and improved the exploitative efficiency of wind.The optimal installation programme of L tip vane as follow:the installation angle is 45 °and the length is 2 m.L tip vane has obvious lifting effect for power and minor effect for thrust under the installation plan,it will not affect the safe operation of the unit.3.The article researched the influence of L tip vane of wind turbine for blade tip pressure distribution and power,when the yaw angle is 10 0,20。30 °,40 °.The results show that the installation of L tip vane reduced the fluctuation of output power and thrust of the wind turbine,improved the fatigue resistance performance of the wind turbine and prolonged the service life of the blade.The influence of L tip vane for the tip pressure differential decreases with the increase of yaw angle.The L tip vane increased the pressure differential between the upper and lower surface of the blade tip,enhanced the torque of wind wheel and plays a role in power’s enlargement within the wind speed 5 m/s～17 m/s.The paper researched the influence of the installation parameters of L tip vane on the aerodynamic performance,revealed that the power increase of L tip vane wind turbine was mainly caused by the improvement of the aerodynamic performance of the blade rather than the increase radius of the wind turbine,obtained an optimal installation plan of L tip vane which provided a reference for the large wind turbine to install the L tip vane.