MIXING AND FLUCTUATIONS IN A TURBULENT WAKE

Abstract

The structure of turbulent wakes of hypersonic bodies is argued to be largely controlled by the combined action of relatively large scale random convective motions, which introduce inhomogeneities in the wake core, and of molecular diffusion aided by turbulent distortions of fluid elements. A previously developed mathematical model representing turbulent wake mixing in terms of a mixing lag is discussed and qualitatively justified in terms of the above described mixing mechanism, and somewhat generalized. Numerical predictions for the magnitude and variation of mass density fluctuations in a relatively low speed wake are obtained by solving a simplified set of equations, in which the lag is represented by an effective mixing boundary, and are in encouraging agreement with the general magnitude and trend observed experimentally, although firm experimental measurements are lacking to-date.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1964
Accession Number
AD0610096

Entities

People

  • Andrew P. Proudian

Tags

Communities of Interest

  • Energy and Power Technologies
  • Weapons Technologies

DTIC Thesaurus Topics

  • Bodies
  • Boundaries
  • Celestial Brightness
  • Chemical Reactions
  • Chemistry
  • Convection
  • Diffusion
  • Equations
  • Flow
  • Free Stream
  • Kinetic Energy
  • Measurement
  • Reynolds Number
  • Stratified Fluids
  • Turbulence
  • Turbulent Flow
  • Turbulent Mixing

Fields of Study

  • Physics

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Theoretical Analysis.

Technology Areas

  • Hypersonics
  • Hypersonics - Hypersonic Flight