212 軸対称鈍頭物体の後流場の渦構造

抄録

The vortical structure of the near wake of an axisymmetric bluff body in the region of low Reynolds number is experimentally investigated. Morel model which is the fundamental shape of a flying body is used as the bluff body. This model has interchangeable after-bodies with slanted bases having slant angles from 0° to 60°.The model is installed in a uniform flow in the test section of the water channel. And the velocity distribution in the near wake is measured by using laser doppler velocimeter. Also the structures of shedding vortices are examined by the flow visualization technique. Behind the model, it was contirmed that there were regular shedding vortices. As the slant angle of the after-body becomes larger, the frequency of the shedding vortices becomes shorter. The remarkable change of the vortex pattern owing to the variation in the slant angle of the after-body could not be confirmed. It was found out that the geometrical form of the vortex was an arch-type with a revolution.