Flow Through a Sudden Enlargement Subjected to Large Amplitude Low Frequency Axial Oscillations.

Abstract

An experimental investigation was undertaken for the case of flow through a sudden expansion subjected to large amplitude low frequency axial oscillations which formed a standing wave in the receiver duct. Measurements included integrated velocity fluctuation amplitudes and velocity and wall pressure fluctuation amplitudes at the wavemaker frequency. Reattachment of the flow drastically attenuates the fluctuation parameters. Oscilloscope traces show a tendency toward flow relaminarisation during the accelerating phase of the cycle, and a turbulent bursting to high turbulence intensity when the time dependent pressure gradient changes from negative to positive. (Author)

Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1973
Accession Number
AD0770581

Entities

People

  • D. Rockwell
  • N. Siddiqui
  • S. Rehmani

Organizations

  • Lehigh University

Tags

DTIC Thesaurus Topics

  • Amplitude
  • Frequency
  • Frequency Shift
  • Intensity
  • Measurement
  • Oscillation
  • Oscilloscopes
  • Pressure Gradients
  • Standing Waves
  • Turbulence
  • Waves

Fields of Study

  • Physics

Readers

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