3942 ピッチング運動とヒービング運動が組合った運動翼に働く非定常推進力(G05-5 生物流体,G05 流体工学)

Abstract

Many studies on unsteady flow around an unsteady airfoil, such as a pitching airfoil and a heaving 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 an unsteady airfoil in pitching and heaving motions has not been understood sufficiently. We have carried out dynamic thrust measurement acting on an unsteady airfoil in pitching and heaving motions at low Reynolds number region, Re=40000. The averaged dynamic thrust during one cycle acting on a combination airfoil at φ=π/2 and π even in low V_p and V_h was more higher that on a pitching airfoil and a heaving airfoil. Especially, the combination airfoil at φ=π generated large thrust during one cycle. The maximum thrust efficiency of dynamic thrust on a combination airfoil was 40% at φ=π/2 and was higher than that on a pitching airfoil and a heaving airfoil.