A novel hybrid two-level and kinetic-eddy simulation model for high Reynolds number wall-bounded turbulent flows

A novel hybrid model for simulation of wall-bounded turbulent flows is developed by blending the two-level simulation (TLS) method [1] in the near-wall inner region with the kinetic-eddy simulation (KES) method [2] in the outer region. TLS is a multi-scale approach, where a field variable is decomposed into its large-scale (LS) and small-scale (SS) components, and both LS and SS fields are obtained explicitly by employing modeling assumptions for the small-scales. It does not employ the notion of spatial filtering and eddy viscosity. KES is a two-equation based model, where transport equations for the local subgrid kinetic energy and length scale are solved, thus allowing the method to approach to very large-eddy simulation (VLES), LES, and direct numerical simulation (DNS) in the limit of resolution of turbulence length scales corresponding to only large scales, grid size, and fully resolved, respectively. The generalized hybrid formulation is evaluated for its capabilities by simulating fully developed turbulent channel flow at different frictional Reynolds number, and comparing with the reference DNS results.

[1] K. A. Kemenov, S. Menon, J. Comput. Phys., 220 (2006), 290-311.
[2] M. Zaki, S. Menon, L. N. Sankar, J. Aircraft, 47 (2010), 805-811.