The Forced Reattachment of the Separated Shear Layer of a Circular Cylinder with Tangential Blowing

Abstract

An experiment was carried out on the aerodynamic characteristics of a circular cylinder with tangential blowing for various blowing positions. In the case that the blowing position is in the separated region, the separated shear layer is forced to reattach to the cylinder surface by the suction effect of the blowing jet. The reattachment takes place suddenly at a certain intensity of the jet depending on the blowing position and results in a discontinuous change of the aerodynamic characteristics. The forced reattachment is effectively promoted by increasing the Reynolds number and the intensity of turbulence in the case of a laminar shear layer but is independent of them in the case of a turbulent shear layer.