The Aerodynamic Characteristics of a Circular Cylinder with Tangential Blowing in Uniform Shear Flows

Abstract

The experimental results of lift and drag acting on a circular cylinder with tangential blowing immersed in a uniform shear flow are presented for seven shear parameters : K=+0. 15, +0. 045, +0. 030, 0, -0. 030, -0. 045, -0. 15 at the Reynolds number 6×10⁴. The effect of the velocity gradient of the uniform shear flow on the characteristic values is discussed for the coefficients of momentum of the blowing ranging from 0 to 0. 4. In this study, we also discuss in depth the contribution of the characteristic values to the lift. These values include the angles and the pressure coefficients of the stagnation point and the separation points as well as the minimum pressure and base pressure. It was found in this study that the shear parameters strongly affected the coefficients of lift and drag, and different starting points for the forced reattachment phenomenon. All the characteristic variables increasing the lift coefficient can be clearly classified into three categories : the first category was influenced only by the shear parameter, the second, only by the location of the tangential jet, and the third, by both parameters. A comparison of various features such as the stagnation point clarifies the contributions of each feature to the lift and drag on the cylinder.