Forced Diffusion of Trailing Vorticity from a Hovering Rotor

A small turbulence generating device was Attached near the tip of a hovering rotor blade In order to alter the structure of the trailing vortex. Stereo particle image velocimetry (PIV) images were used to quantify the wake behind the rotor blade during the first revolution. An analysis of the 3D-velocity field includes a method for accounting for vortex wander. The results show that a major change in the size and intensity of the trailing vortex can be achieved.