Effect of a rapid expansion on the development of compressible free shear layers

J. L. Herrin, J Craig Dutton

Research output: Contribution to conferencePaper

Abstract

Detailed mean velocity and turbulence data have been obtained with a laser Doppler velocimeter for two axisymmetric shear layers downstream of rapid expansions of different strengths. A comparison of the data in the near-field (immediately downstream of separation) and far-field (shear layer approaching self-similarity) is presented, and the fluid dynamic effects of the rapid expansion are ascertained for each regime. In general, the rapid expansion was found to distort the initial mean velocity and turbulence fields in the shear layer such that two distinct regions were evident: an outer region where the turbulent fluctuations are quenched by the expansion, and an inner region where turbulence levels are magnified by the expansion. For the streamwise Reynolds normal stress and primary Reynolds shear stress, the magnitude of the peak turbulence levels increased with increasing strength of the rapid expansion; the transverse normal stress field, however, was only mildly affected by the expansion. Further downstream after the shear layer mean velocity distributions become self-similar, elevated turbulence levels for the more strongly expanded case persist although the relative distribution of turbulence energy between the Reynolds stress components appears unaffected by the strength of the rapid expansion.

Original languageEnglish (US)
StatePublished - Jan 1 1994
EventAIAA Fluid Dynamics Conference, 1994 - Colorado Springs, United States
Duration: Jun 20 1994Jun 23 1994

Other

OtherAIAA Fluid Dynamics Conference, 1994
CountryUnited States
CityColorado Springs
Period6/20/946/23/94

Fingerprint

Turbulence
Laser Doppler velocimeters
Fluid dynamics
Velocity distribution
Shear stress

ASJC Scopus subject areas

  • Aerospace Engineering
  • Engineering (miscellaneous)

Cite this

Herrin, J. L., & Dutton, J. C. (1994). Effect of a rapid expansion on the development of compressible free shear layers. Paper presented at AIAA Fluid Dynamics Conference, 1994, Colorado Springs, United States.

Effect of a rapid expansion on the development of compressible free shear layers. / Herrin, J. L.; Dutton, J Craig.

1994. Paper presented at AIAA Fluid Dynamics Conference, 1994, Colorado Springs, United States.

Research output: Contribution to conferencePaper

Herrin, JL & Dutton, JC 1994, 'Effect of a rapid expansion on the development of compressible free shear layers', Paper presented at AIAA Fluid Dynamics Conference, 1994, Colorado Springs, United States, 6/20/94 - 6/23/94.
Herrin JL, Dutton JC. Effect of a rapid expansion on the development of compressible free shear layers. 1994. Paper presented at AIAA Fluid Dynamics Conference, 1994, Colorado Springs, United States.
Herrin, J. L. ; Dutton, J Craig. / Effect of a rapid expansion on the development of compressible free shear layers. Paper presented at AIAA Fluid Dynamics Conference, 1994, Colorado Springs, United States.
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