Experiments on turbulent boundary layers along a circular cylinder with and without separation

Abstract

Summary: Experiments were conducted in a turbulent boundary-layer near separation along a circular cylinder with the flow in the axial direction. The pressure gradient along the axis of the cylinder could be varied such that it was possible to maintain three boundary-layer configurations close to separation or with regions of reversed flow: 1. A turbulent boundary-layer with skin friction zero. 2. A turbulent boundary layer with a separated region and reattachment further downstream with skin friction zero. 3. A turbulent boundary layer with a region of small but constant skin friction and normal separation. Pressure and skin friction along the cylinder wall,. as well as mean velocity profiles in the boundary-layer, were measured.