Particle image velocimetry measurements of the aerodynamics of a wind turbine

The authors describe an aerodynamic study of flow over a simple commercial wind turbine in wind tunnel experiments using the particle image velocity (PIV) technique. In particular the use of the PIV technique was demonstrated for determining both the characteristics of the tip vortices trailing from consecutive blades of the wind turbine and circulation around the individual blade. These factors are of interest to both helicopter and wind turbine blade design. The experimental apparatus is described as it pertains to the sampling of the periodic but unsteady flow found behind the rotor. Also described are the data processing techniques used to extract velocity, vorticity and circulation measurements from the PIV images