Partially Averaged Navier-Stokes Method: Modeling and Simulation of Low Reynolds Number Effects in Flow Past a Circular Cylinder

Abstract

In variable-resolution (VR) calculations it is sometimes necessary to place the partition between resolved and unresolved scales in the dissipation range. While such a scenario typically happens in low Reynolds number simulations, it can also occur in very highresolution VR simulations of high Reynolds number flows. Most subgrid or VR models tacitly assume cut-off in the inertial scales and, therefore, must be modified to account for the ‘low Reynolds-number’ effect ‐ difference between total and unresolved dissipation. In this paper, we develop a closure strategy for modeling the low Reynolds number effect in the context of the Partially Averaged Navier-Stokes (PANS) VR model. The proposal is tested by computing low and high Reynolds number flows past a circular cylinder. Comparison with experimental data shows that the approach provides the required improvement in low Reynolds number flows.