TITLE

Modeling of plane Couette flow. II. On the spreading of a turbulent spot

AUTHOR(S)
Lagha, Maher
PUB. DATE
October 2007
SOURCE
Physics of Fluids;Oct2007, Vol. 19 Issue 10, p104108
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
In this paper, we study the spreading mechanism of turbulent spots in plane Couette flow, where fluid is sheared between two parallel plates moving in opposite directions. The analysis of the coherent structures on the border between the laminar and turbulent regions reveals the existence of many vortices with wall-normal axes occupying the full gap between the plates. The streamwise component of the velocity field of these vortices is the streaks. Due to their self-advection, these vortices move parallel to the plates. During their motions, they carry the other perturbation components such as the streamwise and spanwise vortices.
ACCESSION #
27370698

Tags: FLUID dynamics;  SHEAR flow;  TURBULENT boundary layer;  LAMINAR boundary layer;  COHERENT states;  TAYLOR vortices

 

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