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Regeneration of near-wall turbulence structuresAn examination of the regeneration mechanisms of near-wall turbulence and an attempt to investigate the critical Reynolds number conjecture of Waleffe & Kim is presented. The basis is an extension of the 'minimal channel' approach of Jimenez and Moin which emphasizes the near-wall region and further reduces the complexity of the turbulent flow. Reduction of the flow Reynolds number to the minimum value which will allow turbulence to be sustained has the effect of reducing the ratio of the largest scales to the smallest scales or, equivalently, of causing the near-wall region to fill more of the area between the channel walls. In addition, since each wall may have an active near-wall region, half of the channel is always somewhat redundant. If a plane Couette flow is instead chosen as the base flow, this redundancy is eliminated: the mean shear of a plane Couette flow has a single sign, and at low Reynolds numbers, the two wall regions share a single set of structures. A minimal flow with these modifications possesses, by construction, the strongest constraints which allow sustained turbulence, producing a greatly simplified flow in which the regeneration process can be examined.
Document ID
19940007836
Acquisition Source
Legacy CDMS
Document Type
Other
Authors
Hamilton, James M.
(Stanford Univ. CA, United States)
Kim, John J.
(Stanford Univ. CA, United States)
Waleffe, Fabian A.
(Stanford Univ. CA, United States)
Date Acquired
September 6, 2013
Publication Date
January 1, 1993
Publication Information
Publication: Annual Research Briefs, 1992
Subject Category
Fluid Mechanics And Heat Transfer
Accession Number
94N12308
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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