抄録
Many studies on unsteady flow around an unsteady airfoil, such as a pitching airfoil, a heaving airfoil and a combination airfoil, at low Reynolds number region have been carried out with experimental and numerical approaches and vortex flow patterns and dynamic thrust of them have been reported. However, the flow field around a moving elastic airfoil and the characteristics of fluid forces acting on it has not been understood sufficiently. In order to clarify the detailed vortex flow structure behind a moving elastic airfoil we have carried out PIV measurement behind a elastic flat plate at Re=4000. The heaving elastic flat plate forms thrust producing vortex streets with vortices accompanied with large vorticities easily, comparing to moving rigid body airfoils. In the wake of a elastic flat plate, jet velocity becomes over 2.0 and the values are greater than that of the moving rigid body airfoils.
