A novel optical method is used to measure the high-frequency (up to 3 MHz) density
fluctuations that precede transition to turbulence within a laminar boundary layer in a …

This paper reports on measurements of freestream nitric oxide (NO) rotational and
vibrational temperatures and partial pressures, collected in the Caltech T5 reflected shock …

Focused laser differential interferometry is used to quantify the free-stream density
perturbations in the T5 reflected-shock tunnel. The investigation of reflected-shock tunnel …

With novel application of optical techniques, the slender-body hypervelocity boundary-layer
instability is characterized in the previously unexplored regime where thermo-chemical …

There has been renewed interest in supersonic modes in hypersonic boundary layers,
which have been previously thought to be insignificant due to their smaller amplitudes than …

Supersonic modes, previously thought to be insignificant due to their smaller amplitude than
Mack's traditional second mode, occur in hypersonic boundary layers when a disturbance …

There has been renewed interest in studying supersonic modes in hypersonic boundary
layers. Recent computational results have shown supersonic modes in hot-wall flows …

View Video Presentation: https://doi. org/10.2514/6.2021-3525. vid We report on
measurements of rotational and vibrational temperature, velocity, and concentrations of nitric …

View Video Presentation: https://doi. org/10.2514/6.2022-0734. vid In this paper, a Q-FLDI
system was constructed to correlate disturbances inside and outside of the boundary layer …

THE prediction of a high-speed boundary-layer transition (BLT) location is critical to
hypersonic vehicle design; this is because the increased skin friction and surface heating …