A stereoscopic Particle Image Velocimetry (PIV) system has been implemented in the Lockheed Martin High Speed Wind Tunnel up to Mach 1.4. This is believed to be the first application of PIV to a production-scale blowdown wind tunnel. A customized particle seeder has delivered a high-density, uniform distribution of particle diameter 1.5 ± 0.1 μm that faithfully track the flow. Particle image diameters were consistently in the optimal range of 1.5 - 3.0 pixels. Three different wind tunnel models were used to test the capabilities of the system. Crossplane measurements on an interceptor missile revealed the vortices shed from upstream canards and their interference with tail fins. Streamwise-plane data of a flow over a weapons bay of a fighter aircraft showed the dependence of the shear layer on geometrical changes in the bay. Measurements of the turbulent wake of an optical turret mounted on the aircraft revealed the aero-optical environment including unsteady fluctuations. PIV data acquisition was successfully integrated into a standard force-and-moment aerodynamic test with minimal impact on testing efficiency, demonstrating the diagnostic's maturity as a reliable wind tunnel instrument.
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