Measurements of Surface Shear Stresses Under a Three-Dimensional Turbulent Boundary Layer Using Oil-Film Laser Interferometry

Abstract

Measurements of surface shear stress magnitude and direction are reported for a three-dimensional, pressure driven, turbulent boundary layer around a wing body junction. Measurements were made using a dual-beam oil film laser interferometer at 56 locations. An iterative procedure was developed which increased the precision of the data extracted from the data records. Skin friction directions computed using a least square error fit were compared to angles obtained from surface oil flows, hot wire anemometry, and LDV measurements. Also, the magnitude of the skin friction coefficients were compared to independently obtained skin friction coefficients. The data agreed to within experimental error outside the effects from the vortex legs present along the side of the wing-body. No accurate data was available for quantitative comparison under the effects of the vortex, but the magnitudes followed the qualitative trends expected. This method failed badly in the region of large three-dimensional effects and requires further study in this area of application. (SDW)

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1990
Accession Number
ADA229494

Entities

People

  • K. G. Ailinger
  • R. L. Simpson

Organizations

  • Virginia Tech

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Ground and Sea Platforms
  • Space

DTIC Thesaurus Topics

  • Boundary Layer
  • Computational Fluid Dynamics
  • Curve Fitting
  • Data Reduction
  • Flow Visualization
  • Fluid Dynamics
  • Fluid Mechanics
  • Geometry
  • Hot Wire
  • Leading Edges
  • Measurement
  • Photodetectors
  • Pressure Distribution
  • Pressure Gradients
  • Refractive Index
  • Two Dimensional
  • Wind Tunnels

Fields of Study

  • Physics

Readers

  • Aerodynamics.
  • Regression Analysis.
  • Tribology (the study of the boundary interaction between sliding surfaces, lubrication, wear and friction).

Technology Areas

  • Directed Energy