Accession Number : ADP009018

Title :   Measurements of Density, Temperature, and Their Fluctuations in Turbulent, Supersonic Flow Using UV Laser Spectroscopy,

Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION MOFFETT FIELD CA AMES RESEARCH CENTER

Personal Author(s) : Fletcher, D. G. ; McKenzie, R. L.

Report Date : 23 JUL 1992

Pagination or Media Count : 6

Abstract : Nonintrusive measurements of density, temperature, and their turbulent fluctuation levels have been obtained in the boundary layer of an unseeded, Mach 2 wind tunnel flow. The spectroscopic techniques that was used to make the measurements is based on the combination of laser-induced oxygen fluorescence and Raman scattering by oxygen and nitrogen from the same laser pulse. Results from this demonstration experiment are compared with previous measurements obtained in the same facility using conventional probes and an earlier spectroscopic technique. Densities and temperatures measured with the current technique agree with the previous surveys to within 3% and 2%, respectively. The fluctuation amplitudes for both variable agree with the measurements obtained using the earlier spectroscopic technique and show evidence of an unsteady, weak shock wave that perturbs the boundary layer. (Author)

Descriptors :   *SUPERSONIC FLOW, *TURBULENT FLOW, *ULTRAVIOLET SPECTROSCOPY, SHOCK WAVES, RAMAN SPECTROSCOPY, OPTICAL IMAGES, COMPARISON, EXPERIMENTAL DATA, BOUNDARY LAYER, FLUX DENSITY, TEMPERATURE GRADIENTS, LASER INDUCED FLUORESCENCE, THERMODYNAMIC PROPERTIES, WIND TUNNEL TESTS.

Subject Categories : Fluid Mechanics
      Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE