Application of FLEET Velocimetry in the JAXA 1 m × 1 m Supersonic Wind Tunnel

Femtosecond laser electronic excitation tagging (FLEET) velocimetry system was developed and installed in the JAXA 1 m × 1 m Supersonic Wind Tunnel. The decay characteristics of the FLEET emission under various air-pressure conditions were obtained prior to the wind-tunnel test, and the appropriate imaging timing was selected accordingly. To evaluate the measurement accuracy of the JAXA’s FLEET system in airflow, the velocity of uniform flows at Mach numbers of 1.4, 2.0, 3.0 and 4.0 was measured. The velocity measured with the FLEET system agreed reasonably well with that calculated by the wind tunnel system, with the difference being less than 2%. AGARD-B, which was the standard model of the wind tunnel, was used for the demonstration of velocity distribution measurement at freestream Mach numbers of 1.4, 2.0, and 3.0. The results clearly showed the influence of the Mach number and spanwise location on the velocity distribution of the wake.