The mechanism of streak formation in near-wall turbulence
The mechanism of streak formation in near-wall turbulence
Two conceptual frameworks for the origin of the streaky pattern in near-wall developed turbulent flows are compared. According to the framework that dominated the research over several decades, the pattern of streaks is dictated by the pattern of wall-normal motions via the lift-up mechanism. Various concepts within this framework describe the wall-normal motions as induced by longitudinal vortices, hairpin vortices, vortex packets, etc. According to the newly emerging conceptual framework, the combined action of lift-up of the mean profile, mean shear, and viscous diffusion has its own pattern-forming properties. The pattern of streaks is dictated by these linear effects to a much greater extent than by the pattern of the wall-normal motions. Numerical results supporting the new conceptual framework are presented. An approximate approach for calculating the streak spacing within the new framework is proposed. It is shown to have a significant predictive ability.
99-131
Chernyshenko, S.I.
6fef97f7-e668-45f7-8fef-7a4cd4cb1fb2
Baig, M.F.
e618bead-e673-4726-a3ad-ee307203a9a0
2005
Chernyshenko, S.I.
6fef97f7-e668-45f7-8fef-7a4cd4cb1fb2
Baig, M.F.
e618bead-e673-4726-a3ad-ee307203a9a0
Chernyshenko, S.I. and Baig, M.F.
(2005)
The mechanism of streak formation in near-wall turbulence.
Journal of Fluid Mechanics, 544 (n/a), .
(doi:10.1017/S0022112005006506).
Abstract
Two conceptual frameworks for the origin of the streaky pattern in near-wall developed turbulent flows are compared. According to the framework that dominated the research over several decades, the pattern of streaks is dictated by the pattern of wall-normal motions via the lift-up mechanism. Various concepts within this framework describe the wall-normal motions as induced by longitudinal vortices, hairpin vortices, vortex packets, etc. According to the newly emerging conceptual framework, the combined action of lift-up of the mean profile, mean shear, and viscous diffusion has its own pattern-forming properties. The pattern of streaks is dictated by these linear effects to a much greater extent than by the pattern of the wall-normal motions. Numerical results supporting the new conceptual framework are presented. An approximate approach for calculating the streak spacing within the new framework is proposed. It is shown to have a significant predictive ability.
This record has no associated files available for download.
More information
Published date: 2005
Identifiers
Local EPrints ID: 23517
URI: http://eprints.soton.ac.uk/id/eprint/23517
ISSN: 0022-1120
PURE UUID: db412cb1-4cf3-40bc-bc06-a99a0f559ccd
Catalogue record
Date deposited: 20 Mar 2006
Last modified: 15 Mar 2024 06:47
Export record
Altmetrics
Contributors
Author:
S.I. Chernyshenko
Author:
M.F. Baig
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics