Explicit small-scale velocity simulation for high-Re turbulent flows. Part II: Non-homogeneous flows

A new two-scale model for large eddy simulation of wall-bounded flows

“…The TLS approach proposed by Kemenov and Menon [56,57] uses a special largescale function in lieu of filtering to separate the large scales from the small scales.…”

“…For computationally efficient implementation of the TLS approach the SS field is simulated on three one-dimensional (1D) orthogonal lines embedded within the LES three-dimensional (3D) grid. Past studies of decaying and forced isotropic turbulence [56], mixing layers [57] and fully developed channel flow [57] have shown that the baseline TLS model can capture important features of high-Re turbulent flows using relatively coarse grids under a wide range of conditions. Therefore, can be extended as a near-wall approach for LES.…”

“…The major objective of this work is to propose a framework which does not suppress the near-wall fluctuations. In this thesis, a new hybrid model that combines a multiscale approach based on TLS [56,57] in the inner region with conventional LES away from the wall is demonstrated. Some earlier attempts of applying the current approach to simulate non-homogeneous flows, such as canonical channel flows and channel flows with adverse pressure gradient, were reported elsewhere [38,37,36].…”

“…The TLS approach has recently been described by Kemenov and Menon [56,57] as a novel approach that utilizes a special scale separation in lieu of spatial filtering that is commonly done in LES. The TLS approach provides a different perspective on turbulence modeling in which small-scales are calculated using a small-scale simulation model instead of modeling the effect of small-scale on the large-scales.…”

LES approach coupled with stochastic forcing of subgrid acceleration in a high-Reynolds-number channel flow

“…The model proposed by Schmidt et al [10] is based on the LES/ODT (One Dimensional Turbulence) coupling [11,12] and provides stochastically the unresolved velocity field as the wall is approached. The approach of Kemenov and Menon [13] is based on the simulation of a turbulent velocity field which is defined by superposition of large-scale and small-scale components. The latter is computed directly on subgrid-scales by a simplified 1D motion equation (in three directions).…”