Abstract
To investigate the dynamic behavior of vortex shedding from a discoid airfoil, which simulates a hand of swimmer, we made an experiment using a wind tunnel. The structure of flow under the pitching motion is measured by particle image velocimetry (PIV). It was cleared that the reduced frequency and the amplitude of pitching motion affect the flow structure. The amplitude of pitching motion gave more prominent effect on the velocity profiles near the back surface of airfoil rather than the reduced frequency. It was shown that the generation of vortices was dependent on the reduced frequency and the growth of vortices was dependent on the amplitude of pitching motion. In addition, it was shown the existence of the suitable range of the reduced frequency and the amplitude for the growth of vortices.
