Chad S. Hale

Date of Award


Document Type


Degree Name

Master of Science


Department of Aeronautics and Astronautics

First Advisor

Rodney Bowersox, PhD


Laser Doppler Velocimetry (LDV) measurements were made to quantify the effect of adverse pressure gradient on the compressible turbulent flow structure in a Mach 2.9 boundary layer (Re/m= 1.75 x 107). Measurements included profiles of 2-D mean velocities, turbulence intensities, Reynolds shear stresses, intermittency, flatness and skewness. In addition, mean strain rates were also measured. The boundary layer measurements were acquired for both flat plate and compression ramp models. LDV measurements were made at two locations on the compression ramp model at 68 cm and 71 cm downstream of the nozzle throat. At these locations, Β ≈ 1.12 and -0.94, respectively. Flow visualization was accomplished by nanosecond shadowgraph and schlieren photography. Results indicate that the adverse pressure gradient increased the Reynolds shear stresses by 190% and turbulence intensities by 24% of the flat plat values. In the favorable pressure gradient region, these quantities were decreased by 52% and 7% with respect to the adverse pressure gradient values, respectively.

AFIT Designator


DTIC Accession Number