平面壁上の有限長円柱の近傍後流

抄録

We describe an experimental study on the process involved in the disappearance of arch vortices shed from a circular cylinder of finite length, and the accompanying changes in the turbulent near wake, as a function of the aspect ratio of a circular cylinder. The experiment was carried out in a circuit-type wind tunnel having a 200 mm×200 mm working section of 2000 mm length at the Reynolds number Re of 9200. The time-mean velocity and turbulence intensities were measured by use of a laser Doppler velocimeter. Vortex formation was observed by flow visualization in a water channel at Re=4600. Consequently. details of the flow pattern in the turbulent near wake behind a circular cylinder were revealed, including information on shedding arch vortices.