Direct Numerical Simulation of Wakes with Virtual Cylinders

Abstract

We use the virtual boundary technique in a context of Direct Numerical Simulation of turbulent flows around cylinders. This approach allows the imposition of a no-slip boundary condition within the flow field by a feed-back unsteady
forcing term added to the momentum equation. In this paper, we consider the flow around a single cylinder with upstream conditions corresponding to a constant velocity flow or a mixing layer flow. Preliminary results show the capabilities of the virtual boundary technique to take complex obstacles into
account realistically by the use of a simple Cartesian grid along with accurate finite difference method.