Femtosecond Laser Electronic Excitation Tagging (FLEET) is a non-intrusive optical diagnostic technique that has been demonstrated to provide direct measurement of velocity and other transport properties in unseeded air and nitrogen flows. A portable FLEET system that uses a single laser for production of N_2 tracers, and a single camera for tracking their motion in real time has been developed and deployed. The system performance for high speed velocimetry in unseeded nitrogen flow has been evaluated at the AEDC Hypervelocity Wind Tunnel 9. Time resolved FLEET velocity measurements were performed during 21 tunnel runs at Mach 10 and 14, both in freestream and in a turbulent boundary layer. The freestream velocities measured with FLEET displayed excellent agreement with the velocities computed using the standard Tunnel 9 data reduction methodology. The turbulent boundary layer velocity profiles measured with FLEET also showed good agreement with PIV measurements and boundary layer theory.
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