Experiments in Fluids

, Volume 37, Issue 3, pp 438–454

Quantitative visualization of compressible turbulent shear flows using condensate-enhanced Rayleigh scattering

  • J. Poggie
  • P. J. Erbland
  • A. J. Smits
  • R. B. Miles
Review Article

DOI: 10.1007/s00348-004-0828-9

Cite this article as:
Poggie, J., Erbland, P.J., Smits, A.J. et al. Exp Fluids (2004) 37: 438. doi:10.1007/s00348-004-0828-9

Abstract

This paper describes several flow visualization experiments carried out in Mach 3 and Mach 8 turbulent shear flows. The experimental technique was based on laser scattering from particles of H2O or CO2 condensate that form in the wind tunnel nozzle expansion process. The condensate particles vaporize extremely rapidly on entering the relatively hot fluid within a turbulent structure, so that a sharp vaporization interface marks the outer edge of the rotational shear layer fluid. Calculations indicate that the observed thin interface corresponds to a particle size of 10 nm or less, which is consistent with optical measurements, and that particles of this size track the fluid motions well. Further, calculations and experiments show that the freestream concentration of condensate required for flow visualization has only a small effect on the wind tunnel pressure distribution. Statistics based on the image data were compared to corresponding results from probe measurements and agreement was obtained in statistical measures of speed, scale, and orientation of the large-scale structures in the shear layer turbulence. The condensate-enhanced Rayleigh scattering technique is judged to be a useful tool for quantitative studies of shear layer structure, particularly for identifying the instantaneous boundary layer edge and for extracting comparative information on the large-scale structures represented there.

Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  • J. Poggie
    • 1
  • P. J. Erbland
    • 1
  • A. J. Smits
    • 2
  • R. B. Miles
    • 2
  1. 1.Aeronautical Sciences Division, Air Vehicles DirectorateAir Force Research LaboratoryWright-Patterson AFBUSA
  2. 2.Department of Mechanical and Aerospace EngineeringPrinceton UniversityPrincetonUSA