A new-generation wall modeling approach for LES of non-equilibrium turbulent wall-bounded flows

Abstract

SOW A new wall modeling approach for Large Eddy Simulation (LES) will be developed and testedon various turbulent wall-bounded flows. The approach is based on a recent theoreticaldevelopment that arose as part of the soon-to-finish ONR project (N00014-17-1-2937). It enablesus to rigorously separate quasi-equilibrium and non-equilibrium timescales in the relationshipbetween wall stress and the LES-resolved flow away from the wall. The slow part takes the formof a temporal relaxation equation while the rapid part is based on a relationship between wallstress and backward temporal convolution derived from a generalized viscous Stokes problem.As part of the proposed two-year project, the wall model theory and formulation will becompleted and the model applied to wall-bounded flows of increasing complexity: channel flowsubjected to time-varying streamwise pressure gradients (step function, ramp, oscillatory), timevaryingspanwise pressure gradient (step function, ramp, oscillatory), as well as to a spatiallydeveloping boundary later with suction and blowing, including a separation bubble, at very highReynolds numbers. Together with the machine-learning based transition wall-modeling approachdeveloped in the recent ONR project, this project aims to culminate with a theoretically rigorousand practically robust wall model that can be applied to LES across various flow regimes, inparticular to strongly non-equilibrium flows including separated regions.

Document Details

Document Type
DoD Grant Award
Publication Date
Feb 02, 2021
Source ID
N000142112162

Entities

People

  • Charles Meneveau

Organizations

  • Johns Hopkins University
  • Office of Naval Research
  • United States Navy

Tags

Fields of Study

  • Physics

Readers

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

Technology Areas

  • AI & ML
  • AI & ML - Bayesian Inference
  • AI & ML - Machine Learning Algorithms