Experiments on Management of Free-Stream Turbulence

Abstract

The effects of various passive devices (screens, perforated plates, porous foam, and honeycomb-like matrices formed with closely packed plastic drinking straws) on free-stream turbulence and mean velocity profiles are studied in air with hot-wire anemonetry and in water using hydrogen-bubbles visualization. These 'turbulence manipulators' are viewed as operators which suppress the level of the incoming turbulence and generate, primarily through documented instabilities, new turbulences with scales characteristic of the device and its shear layers. In this sense these manipulators can be used to control, manage and/or modify the incoming turbulence flow to yield the one appropriate to the application.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1972
Accession Number
AD0749891

Entities

People

  • H. M. Nagib
  • R. I. Loehrke

Organizations

  • Illinois Institute of Technology

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Weapons Technologies

DTIC Thesaurus Topics

  • Boundary Layer
  • Computational Fluid Dynamics
  • Elements
  • Flow Visualization
  • Fluid Dynamics
  • Fluid Flow
  • Fluid Mechanics
  • Free Stream
  • Frequency
  • Hot Wire
  • Measurement
  • Mechanical Properties
  • Mechanics
  • Reynolds Number
  • Turbulence
  • Turbulent Flow
  • Turbulent Mixing

Fields of Study

  • Physics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Fluid Dynamics.
  • Reinforced Composite Materials