Experimental Study of Unsteady Separating Turbulent Boundary Layers.

Abstract

A detailed experimental study of two large amplitude unsteady freestream flows and a third unsteady flow produced by an oscillating roof damper is reported. Detailed ensemble-averaged velocity and turbulence measurements were made using hot-wire and laser anemometers. While the primary function of this report is to present and document these data, some discussion of the results and a number of data plots are presented. The reduced data are available on computer diskettes. Upstream of detachment at the phases with no flow reversal, the flows are quasi-steady. For the large amplitude flows, at low velocity phases some flow reversal occurs upstream of detachment, which was not observed in the moderate amplitude flow studied by Simpson et al. (1983). After the beginning of detachment, large amplitude and phase variations develop through each flow. Huge backflow velocities, as large as free-stream, were measured. Keywords: Unsteady flows, Laser anemometry, Turbulence, Separation.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1988
Accession Number
ADA192997

Entities

People

  • N. K. Agarwal
  • R. L. Simpson

Organizations

  • Virginia Tech

Tags

Communities of Interest

  • Materials and Manufacturing Processes
  • Sensors
  • Space

DTIC Thesaurus Topics

  • Amplitude
  • Boundary Layer
  • Classification
  • Computational Fluid Dynamics
  • Flow
  • Fluid Dynamics
  • Fluid Flow
  • Free Stream
  • Hot Wire Anemometers
  • Intensity
  • Laser Anemometers
  • Measurement
  • Plastic Explosives
  • Reynolds Number
  • Steady Flow
  • Turbulent Mixing
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Fluid Mechanics and Fluid Dynamics.

Technology Areas

  • Directed Energy