Aerodynamic Investigation Of Wind Turbine Blades And Airfoils With Vortex Generators

The effects of vortex generators on aerodynamic characteristics of the wind turbine is presented. Aerodynamic performance of wind turbine dedicated thick airfoils CAS-W2-350 and CAS-W2-400 is studied experimentally. The measurement focuses on the effects of chord-wise position, height, span-wise spacing between neighbor vortex generators and double rows of vortex generators to the aerodynamic characteristics of the airfoils. After that, vortex generators are installed on an 100 kW wind turbine and the power characteristics of the wind turbine are tested.In wind tunnel experiments, the influence of the vortex generator on the lift coefficient and drag coefficient at different angles of attack is investigated through measuring the surface pressure. With the installation position of the vortex generators moved to the leading edge, the maximum lift coefficient and the stall angle of attack becomes higher and the lift coefficient becomes lower at small angle of attack (0o20o). The dump of the lift coefficient may occur when the position close to the leading edge. The height of the vortex generators has different effect on the airfoil aerodynamic performance when the position of the vortex generator is different. If the position is close to the leading edge(x<20%c), the lift coefficient may dump at large angle of attack. If the position is remote to the leading edge, the height of the vortex generators has little influence on the aerodynamic characteristics of the airfoils. The large span-wise spacing of the vortex generators may break the flow of the boundary layer and leads to the lift coefficient of the airfoil lower. The optimum spacing of the vortex generators is 8 times height of the vortex generators. When the span-wise spacing of the vortex generators is small, the double row vortex generators will reduce the lift coefficient of the airfoil. And the interaction between the second row is farther from the first row, the lift coefficient becomes lower. When the span-wise spacing of the vortex generator is large, double rows of vortex generators will increase the lift coefficient of the airfoil. However, under the current experimental conditions, the lift coefficient become lower compared to the single row vortex generators with optimal span-wise spacing, the lift coefficient become lower.A set of optimized vortex generators for the 100 kW wind turbine was installed and then the field measurement was conducted. This thesis focuses on testing methods and the post-process of data, such as average method and yaw error corrections. The scatter plot of the power to the wind speed and the power coefficient curve at the standard air density are presented.