VTechWorks staff will be away for the Thanksgiving holiday beginning at noon on Wednesday, November 22, through Friday, November 24, and will not be replying to requests during this time. Thank you for your patience, and happy holidays!
Measurements of surface shear stresses under a three-dimensional turbulent boundary layer using oil-film laser interferometry
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.