Maintenance of the Near-Wall Cycle of Turbulence for Hybrid RANS/LES of Fully-Developed Channel Flow

Abstract

Hybrid RANS/LES modeling of near-wall turbulence is investigated for fully-developed turbulent channel flow under very coarse resolution, a resolution not resolving the longitudinal eddies of the buffer layer in near-wall flow but not coarse enough to encompass an "effective" ensemble of eddies to give RANS. Without bursting from the buffer layer, the partially-resolved turbulence is suppressed. We model the effects of the buffer-layer eddies using a field of white noise and show that the core flow is able to extract energy from these artificial fluctuations to organize turbulence eddies that maintain a physical turbulence mixing. Results for Re% 640, based on the channel half-height and on the friction velocity, are presented. Mean-velocity and root-mean-square statistics are compared to results from higher resolution simulations.

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Document Details

Document Type
Technical Report
Publication Date
Aug 01, 2001
Accession Number
ADP013707

Entities

People

  • Frank J. Zajaczkowski
  • Leonard J. Peltier

Organizations

  • Pennsylvania State University

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Channel Flow
  • Diffusion
  • Diffusivity
  • Equations
  • Flow
  • Flow Fields
  • Grids
  • Large Eddy Simulation
  • Navier Stokes Equations
  • Pressure Gradients
  • Reynolds Number
  • Statistics
  • Strain Rate
  • Technical Information Centers
  • Transfer Functions
  • Turbulence
  • White Noise

Fields of Study

  • Physics

Readers

  • Computational Fluid Dynamics (CFD)
  • Fluid Mechanics and Fluid Dynamics.