Electromagnetic Turbulence Control: Salt Water Experiments on an Axisymmetric Body

Abstract

The control of turbulence in a turbulent boundary layer developing over a small axisymmetric cylindrical body in salt water at a moderate Reynolds number is considered in this report. Because near-wall turbulence production has a quasicyclic nature, an attempt is made to perturb the process by means of a periodic Lorenz force. A method of measuring the change in drag due to applied perturbations on a floating cylinder immersed in electrically charged salt water has been developed, and laser Doppler velocimetry measurements of changes in the near-wall mean velocity and turbulence have been carried out. Wall-pressure measurements have also been carried out to determine the effects of perturbation. The skewness and kurtosis of the wall-pressure fluctuation signal were found to increase slowly with the frequency of the Lorenz power pulsing to the microtiles. This pulsing leads to an amplification of wall-pressure spectrum power, which, although weak, provides support to the wall-layer resonance mechanism of the proposed microtiles.

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Document Details

Document Type
Technical Report
Publication Date
Oct 15, 2001
Accession Number
ADA398717

Entities

People

  • Daniel P. Thivierge
  • John M. Castano
  • Joseph Stupak
  • Promide R. Bandyopadhyay
  • William H. Nedderman

Organizations

  • Naval Undersea Warfare Center

Tags

Communities of Interest

  • Energy and Power Technologies
  • Sensors
  • Weapons Technologies

DTIC Thesaurus Topics

  • Boundary Layer
  • Circuit Boards
  • Drag Reduction
  • Electromagnetic Fields
  • Flow Visualization
  • Fluid Dynamics
  • Fluid Flow
  • Fluid Mechanics
  • Frequency
  • Magnetic Fields
  • Measurement
  • Mechanics
  • Physics
  • Pressure Measurement
  • Production
  • Reynolds Number
  • Salt Water

Fields of Study

  • Physics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Fluid Mechanics and Fluid Dynamics.
  • Thermal Physics or Thermal Science.

Technology Areas

  • Directed Energy