PLANAR RAYLEIGH SCATTERING RESULTS IN HELIUM/AIR MIXING EXPERIMENTS IN A MACH 6 WIND TUNNEL
by
B. Shirinzadeh, R. Jeffrey Balla, M. E. Hillard, J. B. Anders, and?R. J. Exton NASA Langley Research Center
Hampton, VA 23665
and
I. A. Waitz
California Institute of Technology
Pasadena, CA 91125

ABSTRACT

Planar Rayleigh scattering measurements using an ArF-excimer?laser have been performed to investigate helium mixing into air at?supersonic speeds. The capability of the Rayleigh scattering technique for flow?visualization of a turbulent environment is demonstrated in a large-scale, Mach 6?facility. The detection limit obtained with the present setup indicates that?planar, quantitative measurements of density can be made over a large cross sectional?area (5 cm by 10 cm) of the flow field in the absence of clusters.