A mechanism for streamwise localisation of nonlinear waves in shear flows
نویسندگان
چکیده
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.
منابع مشابه
Mechanism for streamwise localisation in 2D plane-Poiseuille flow
Turbulent flows are ubiquitous both in nature and in engineering applications, with far-reaching implications. Turbulence in wall bounded shear flows such as that in pipes, channels and boundary layers feature turbulent transition at Reynolds numbers for which the laminar flow is linearly stable [1], and often do so in the form of discrete patches of turbulence surrounded by quiescent fluid [2]...
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