Open AccessTurbulence intensities in large-eddy simulation of wall-bounded flows
Author(s) -
H. Jane Bae,
Adrián Lozano-Durán,
Sanjeeb Bose,
Parviz Moin
Publication year - 2018
Publication title -
physical review fluids
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.244
H-Index - 37
eISSN - 2469-9918
pISSN - 2469-990X
DOI - 10.1103/physrevfluids.3.014610
Subject(s) - turbulence , large eddy simulation , mechanics , turbulence kinetic energy , context (archaeology) , physics , turbulence modeling , bounded function , boundary value problem , meteorology , geology , mathematics , mathematical analysis , paleontology , quantum mechanics
A persistent problem in wall-bounded large-eddy simulations (LES) with Dirichlet no-slip boundary conditions is that the near-wall streamwise velocity fluctuations are overpredicted, while those in the wall-normal and spanwise directions are underpredicted. The problem may become particularly pronounced when the near-wall region is underresolved. The prediction of the fluctuations is known to improve for wall-modeled LES, where the no-slip boundary condition at the wall is typically replaced by Neumann and no-transpiration conditions for the wall-parallel and wall-normal velocities, respectively. However, the turbulence intensity peaks are sensitive to the grid resolution and the prediction may degrade when the grid is refined. In the present study, a physical explanation of this phenomena is offered in terms of the behavior of the near-wall streaks. We also show that further improvements are achieved by introducing a Robin (slip) boundary condition with transpiration instead of the Neumann condition. By using a slip condition, the inner energy production peak is damped, and the blocking effect of the wall is relaxed such that the splatting of eddies at the wall is mitigated. As a consequence, the slip boundary condition provides an accurate and consistent prediction of the turbulence intensities regardless of the near-wall resolution.