抄録
The purpose of this study is to clarify the influence of interaction between deformable surface and flow field. Generally speaking, Dolphin could swim fast because of oscillated stomach skin. Cylinder models having an elasto-flexible surface were used to simulate the skin of marine animal. These cylinders were placed in water tunnel, and using laser light sheet method to visualize deformation of its cross sectional form, pattern of vortex shedding from the model, flow separation point. Vorticity and hydrodynamical forces were measured. As a result, three different patterns of travelling wave generation on the surface of elasto-flexible cylinder were observed. Separation points moved to downward more compared with the rigid one. And streak line in the vicinity of the wave is broken by new generated wave and small vortexes shed simultaneously from the surface. Distribution of vorticity around the cylinder was clearly different from that of the rigid one. The cylinder, on which travelling waves appear on the surface, has shown about 10% smaller hydrodynamical drag than the rigid cylinder.