A variational multiscale method for the large eddy simulation of compressible turbulent flows on unstructured meshes––application to vortex shedding

Energy transfers and spectral eddy viscosity in large-eddy simulations of homogeneous isotropic turbulence: Comparison of dynamic Smagorinsky and multiscale models over a range of discretizations

“…The method has a variational basis, as it relies on "projecting" the subgrid model onto the fine-scale motions, 10 and it was shown to outperform conventional LES models in Hughes et al 9 It appeared that extracting energy only from high wave number modes led to better results than formulations which extract energy from all modes. Subsequent studies have also confirmed the good behavior of the variational multiscale method on a variety of problems: see Hughes, Oberai, and Mazzei, 11 Winckelmans and Jeanmart, 12 Oberai and Hughes, 13 Farhat and Koobus, 14 Jeanmart and Winckelmans, 15 Holmen et al, 16 Koobus and Farhat,17 Ramakrishnan and Collis. [18][19][20][21] In this work, the spectral eddy viscosities for the conventional dynamic Smagorinsky model and the variational multiscale model are calculated and examined for a range of discretizations.…”

The role of continuity in residual-based variational multiscale modeling of turbulence

“…For a summary of the early literature on stabilized methods see Brooks and Hughes [10]. Recent work on stabilized methods is presented in [1,8,9,11,14,[18][19][20][21]28,33,[41][42][43].…”

Variational Multiscale LES and Hybrid RANS/LES Parallel Simulation of Complex Unsteady Flows

“…In this paper, we consider the Koobus-Farhat VMS implementation [13] for the simulation of compressible turbulent flows. It uses the flow variable decomposition [6]: …”

“…The VMS-LES approach (even with simple subgrid scale models as Smagorinsky's model) and dynamic LES models have shown similar order of accuracy, but the former is less computationally expensive and does not require any ad hoc treatement (smoothing and clipping of the dynamic constant, as usually required with dynamic LES models) in order to avoid stability problems. In this work, we consider the VMS-LES implementation presented in [13] for the simulation of compressible turbulent flows on unstructured grids within a mixed finite volume/finite element framwork. We investigate the effect of subgrid scale models in our VMS-LES method for the simulation of a bluff-body flow.…”