The Effect of Uniform Blowing on the Flow Past a Circular Cylinder

Abstract

This work describes blowing through the whole surface of a porous circular cylinder for the control of the near wake dynamics and the thermal protection of the surface. The flow past the cylinder is numerically studied and the blowing is modeled. Comparisons with experimental data are used for validation. It is shown that the blowing tends to increase the boundary layer thickness, to promote its separation and to decrease the viscous drag induced. Similarly, the convective heat transfer is lowered, and in the case of a nonisothermal blowing, the surface is very effectively protected from the hot free stream flow. The near wake is also affected. The vortex shedding frequency is shown to decrease when blowing occurs and a qualitative model is presented to identify the different mechanisms.