A Near-Wall Two-Equation Model for Compressible Turbulent Flows

Abstract

A near-wall two-equation turbulence model of the K - epsilon type is developed for the description of high-speed compressible flows. The Favre- averaged equations of motion are solved in conjunction with modeled transport equations for the turbulent kinetic energy and solenoidal dissipation wherein a variable density extension of the asymptotically consistent near-wall model of So and co-workers is supplemented with new dilatational models. The resulting compressible two-equation model is tested in the supersonic flat plate boundary layer - with an adiabatic wall and with wall cooling - for Mach numbers as large as 10. Direct comparisons of the predictions of the new model with raw experimental data and with results from the K - omega model indicate that it performs well for a wide range of Mach numbers. The surprising finding is that the Morkovin hypothesis, where turbulent dilatational terms are neglected, works well at high Mach numbers provided that the near wall model is asymptotically consistent. Instances where the model predictions deviate from the experiments appear to be attributable to the assumption of constant turbulent Prandtl number - a deficiency that will be addressed in a future paper.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1991
Accession Number
ADA244348

Entities

People

  • C. G. Speziale
  • H. S. Zhang
  • R. M. So
  • Y. G. Lai

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Boltzmann Equation
  • Boundary Layer
  • Compressible Flow
  • Computational Fluid Dynamics
  • Engineering
  • Equations
  • Equations Of Motion
  • Flow
  • Fluid Dynamics
  • Fluid Flow
  • Heat Transfer
  • Kinetic Energy
  • Mach Number
  • Prandtl Number
  • Turbulence
  • Turbulent Flow
  • Turbulent Mixing

Fields of Study

  • Physics

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Regression Analysis.

Technology Areas

  • Hypersonics
  • Hypersonics - Hypersonic Flow