Cinematic piv of a turbulent free shear layer

Tom Oakley, Eric Loth, Ronald Adrian

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

The objective of this research is to gain new information about a fundamental turbulent planar free shear layer through use of a recently developed diagnostic technique: cinematic Particle Image Velocimetry (PIV). This is accomplished with an argonion laser, a scanning mirror and a 35 mm movie camera. The water shear layer under investigation has a velocity ratio of 0. 22 and a Reynolds number based on velocity thickness and AU of 28, 000. The experimental data obtained by cinematic PIV yields a combined spatial and temporal evolution of the two-dimensional shear layer velocity and spanwise vorticity fields. A simple optimization of the experimental parameters was completed to allow maximum resolution with minimum uncertainty levels. The detailed structure of the shear layer was very different from previous low Reynolds number flows in that the classical well defined eddies and braids were replaced with complex three-dimensional agglomerated vortices of both signs. The velocity field evolution was also notably different from that of the passive scalar field, where the former exhibited stronger temporal variations and reduced spatial coherency. Preliminary temporal and spatial correlations also reveal transverse distributions of integral scales and convection velocities based on streamwise velocity perturbations.

Original languageEnglish (US)
Title of host publicationAIAA Fluid Dynamics Conference, 1994
PublisherAmerican Institute of Aeronautics and Astronautics Inc, AIAA
StatePublished - 1994
Externally publishedYes
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

Velocity measurement
Reynolds number
Vorticity
Mirrors
Vortex flow
Cameras
Scanning
Lasers
Water
Uncertainty
Convection

ASJC Scopus subject areas

  • Aerospace Engineering
  • Engineering (miscellaneous)

Cite this

Oakley, T., Loth, E., & Adrian, R. (1994). Cinematic piv of a turbulent free shear layer. In AIAA Fluid Dynamics Conference, 1994 [AIAA 94-2298] American Institute of Aeronautics and Astronautics Inc, AIAA.

Cinematic piv of a turbulent free shear layer. / Oakley, Tom; Loth, Eric; Adrian, Ronald.

AIAA Fluid Dynamics Conference, 1994. American Institute of Aeronautics and Astronautics Inc, AIAA, 1994. AIAA 94-2298.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Oakley, T, Loth, E & Adrian, R 1994, Cinematic piv of a turbulent free shear layer. in AIAA Fluid Dynamics Conference, 1994., AIAA 94-2298, American Institute of Aeronautics and Astronautics Inc, AIAA, AIAA Fluid Dynamics Conference, 1994, Colorado Springs, United States, 6/20/94.
Oakley T, Loth E, Adrian R. Cinematic piv of a turbulent free shear layer. In AIAA Fluid Dynamics Conference, 1994. American Institute of Aeronautics and Astronautics Inc, AIAA. 1994. AIAA 94-2298
Oakley, Tom ; Loth, Eric ; Adrian, Ronald. / Cinematic piv of a turbulent free shear layer. AIAA Fluid Dynamics Conference, 1994. American Institute of Aeronautics and Astronautics Inc, AIAA, 1994.
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