3D Vector Wavelet-Based Subgrid Scale Model for LES of Nonequilibrium Turbulence.

Abstract

We have laid the foundation to develop and validate LES using wavelets as a functional basis and based on subgrid scale (SGS) modeling using vector wavelets. Wavelet LES (WLES) consists of subgridscale model equations (SSM) and space-resolved model (SRM) equations. Using a vector wavelet decomposition of the velocity field a simple model for locally isotropic turbulence has been derived from the Navier-Stokes equation. This model, which involves no empirical or adhoc parameter Incorporates nonlocal inter-scale interactions, reveals backscatter and can be applied to represent small-scale turbulence in LES schemes. Stationary solutions of the model equation & produce the Kolmogorov k(5/3) inertial spectrum and the k(4) infra-red spectrum. We have completed derivation of the SRM equations based on the helical wave decomposition. We will test the SRM equations using the computational resources in this NAS operational year. A wavelet-based subgrid-scale model (WSSM) will be generalized to account for anisotropic and inhomogeneous turbulence in wall-bounded flows and will employ a nonuniform grid to resolve the near-wall structures. (AN)

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Document Details

Document Type
Technical Report
Publication Date
Apr 11, 1995
Accession Number
ADA299639

Entities

People

  • Fazle Hussain
  • Valery Zimin

Organizations

  • University of Houston

Tags

DTIC Thesaurus Topics

  • Backscattering
  • Boundary Layer
  • Computational Fluid Dynamics
  • Decomposition
  • Differential Equations
  • Equations
  • Fluid Dynamics
  • Fluid Flow
  • Kinetic Energy
  • Large Eddy Simulation
  • Navier Stokes Equations
  • Pipe Flow
  • Scale Models
  • Spectra
  • Stratified Fluids
  • Turbulence
  • Turbulent Boundary Layer

Readers

  • Computational Fluid Dynamics (CFD)
  • Computational Modeling and Simulation
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering

Technology Areas

  • Space