INITIAL FLOW PAST AN IMPULSIVELY STARTED CIRCULAR CYLINDER.

Abstract

The details of flow immediately after the motion of cylinder were studied to make clear the phenomena of the initial separation and the growth of separation vorticies. A hydrogen bubble technique and an electrolysis method were used to visualize the flow in the boundary layer and in the near wake. Thickness of the boundary layers and reversed flow region together with the scale of the vortex and the convective transfer of vorticity generated on the cylinder surface were measured accurately. The time and location of occurrence of initial separation were investigated experimentally in relation to the existing theories.