Large-Eddy Simulation of Transitional Channel Flow

Abstract

A large-eddy simulation (LES) of transition in plane channel flow has been carried out. The LES results have been compared with those of a fine direct numerical simulations (DNS), and with those of a coarse DNS that uses the same mesh as the LES, but no residual stress model. While at the early stages of transition LES, and coarse DNS give the same results, the presence of the residual stress model was found to be necessary to predict accurately mean velocity and Reynolds stress profiles during the late stages of transition (after the second spike stage). The evolution of single Fourier modes is also predicted more accurately by the LES than by the DNS. As small scales are generated, the dissapative character of the residual stress starts to reproduce correctly the energy cascade; as transition progresses, then, and the flow approaches its fully developed turbulent state, the subgrid scales tend towards equilibrium and the model becomes more accurate. (MM)

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1990
Accession Number
ADA229672

Entities

People

  • Thomas A. Zang
  • Ugo Piomelli

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Boundary Layer
  • Channel Flow
  • Computational Fluid Dynamics
  • Computers
  • Energy Transfer
  • Engineering
  • Equations
  • Flow
  • Fluid Dynamics
  • Fluid Mechanics
  • Large Eddy Simulation
  • Mechanical Properties
  • Mechanics
  • Residual Stress
  • Simulations
  • Stresses
  • Turbulent Flow

Fields of Study

  • Physics

Readers

  • Computational Fluid Dynamics (CFD)
  • Fluid Dynamics.
  • Materials Science (Mechanical Engineering).