21012 Vortex Behavior in the Wake of 3-Dimensional Oscillating Airfoil

In this study, unsteady fluid forces acting on a three dimensional airfoil (a discoid airfoil) simulating a human hand and the vortical flow fields were investigated in the sinusoidal pitching motion. The fluid forces were measured by using the ring structure balance system. The measurements of flow field around the airfoil were carried out by the hot-wire anemometry and the PIV (Particle Image Velocimetry) technique. The unsteady fluid forces were changed periodically during the pitching motion due to the vortex shedding from the airfoil edge. The strength of shedding vortex increases with increasing pitching frequency.