Dynamic Structure Les Models

Abstract

A new dynamic structure (DS) approach for large eddy simulation modeling has been developed. The approach uses a tensor coefficient for the structure of the sub-grid stresses and a sub-grid kinetic energy for the magnitude of the stresses. The tensor coefficient is obtained directly from using the common dynamic approach' using the Germano identity. The sub-grid kinetic energy is obtained from a transport equation. The objectives of the program are: (i) to develop the DS approach for scalar transport with potential application to heat transfer problems and (ii) develop and test the DS formulation for rotating turbulence. The approach offers several significant advantages over existing approaches including: (i) no turbulent viscosity is used, (ii) an energy budget is enforced, (iii) very good prediction of the actual sub-grid stresses is obtained, and (iv) the model rests on a sound mathematical foundation that observes solvability constraints. New subgrid scale models are developed for subgrid scalar flux, subgrid scalar dissipation and subgrid scale energy dissipation. Models are evaluated a-priori using available DNS data for decaying isotropic turbulence, incompressible channel and Couette flows, and non-reacting mixing layer. A posteriori tests include LES of decaying isotropic turbulence and LES of incompressible mixing layer.

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Document Details

Document Type
Technical Report
Publication Date
Sep 30, 2004
Accession Number
ADA430468

Entities

People

  • Christopher J. Rutland

Organizations

  • University of Wisconsin–Madison

Tags

DTIC Thesaurus Topics

  • Boltzmann Equation
  • Coefficients
  • Computational Fluid Dynamics
  • Computational Science
  • Energy
  • Energy Transfer
  • Equations
  • Flow
  • Fluid Dynamics
  • Fluid Flow
  • Heat Transfer
  • Kinetic Energy
  • Large Eddy Simulation
  • Mechanical Engineering
  • Scale Models
  • Simulations
  • Turbulent Mixing

Fields of Study

  • Physics

Readers

  • Computational Fluid Dynamics (CFD)
  • Fluid Dynamics.