A mechanism for streamwise localisation of nonlinear waves in shear flows. (17th August 2015)

• Record Type: Journal Article
• Authors: Mellibovsky, Fernando; Meseguer, Alvaro
• Is Part Of: Journal of fluid mechanics. Volume 779(2015:Sep.)
• Publication Date: 2015-08-17
• Subjects: bifurcation, -- instability, -- turbulent transition; Fluid mechanics -- Periodicals; 532.005
• DOI: 10.1017/jfm.2015.440
• Languages: English
• ISSNs: 0022-1120

Abstract

Abstract : We present the complete unfolding of streamwise localisation in a paradigm of extended shear flows, namely two-dimensional plane Poiseuille flow. Exact solutions of the Navier–Stokes equations are computed numerically and tracked in the streamwise wavenumber–Reynolds number parameter space to identify and describe the fundamental mechanism behind streamwise localisation, a ubiquitous feature of shear flow turbulence. Unlike shear flow spanwise localisation, streamwise localisation does not follow the snaking mechanism demonstrated for plane Couette flow.