Decrease of the effective Reynolds number with eddy-viscosity subgrid-scale modeling

The effects of subgrid modeling based on eddy viscosity in large-eddy simulation (LES) of turbulent flows were discussed. The study was focused on three flow features that appears to depend on the effective Reynolds number of the computed jets which include the centerline mean axial velocity, turbulence intensity on the jet axis, and the sound spectrum in the sideline direction from the jet. The effective flow Reynolds number is found to be decreased using the dynamic Smagorinsky model, whereas it seems to be preserved and correspond to initial jet conditions. The result shows that sound spectrum from LESdsm is similar to those at low Reynolds number, in accordance with the decrease of the effective Reynolds number using Eddy velocity.