Structure-Based Turbulence Model.

Abstract

Models of turbulence for complex engineering flows need to be able to span the full range of deformation rates from slow, where eddy viscosity models (e.g.k-e) relating the turbulent stress to the mean strain rate are valid, to rapid deformations where the stresses are determined by the amount of strain. In order to build a one-point turbulence model that can match Rapid Distortion Theory (RDT) when appropriate, new concepts are needed to parameterize the turbulence structure. This research, which builds upon these new concepts, develops a new structure-based model for RDT of homogeneous turbulence that will be used as the backbone of a more general model for both slow and rapid distortion in general turbulent flows. The model has been tested against exact IQDT for a very wide variety flows involving various complex combinations of mean strain and rotation. Adequate agreement is found in all cases and excellent agreement in most. The work is a key step towards a more general, robust engineering model for predicting turbulent flows.

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Document Details

Document Type
Technical Report
Publication Date
May 24, 1995
Accession Number
ADA299613

Entities

People

  • William C. Reynolds

Organizations

  • Stanford University

Tags

Communities of Interest

  • Human Systems

DTIC Thesaurus Topics

  • Boundary Layer
  • Computational Fluid Dynamics
  • Distortion
  • Eddies (Fluid Mechanics)
  • Engineering
  • Equations
  • Flow
  • Fluid Dynamics
  • Fluid Flow
  • Fluid Mechanics
  • Mechanical Engineering
  • Mechanical Properties
  • Mechanics
  • Strain Rate
  • Turbulence
  • Turbulent Flow
  • Two Dimensional

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Mechanical Engineering/Mechanics of Materials.
  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers

Technology Areas

  • AI & ML
  • AI & ML - Bayesian Inference
  • AI & ML - Neural Networks