Turbulent–laminar patterns in shear flows without walls

  title={Turbulent–laminar patterns in shear flows without walls},
  author={Matthew Chantry and Laurette S. Tuckerman and Dwight Barkley},
  journal={Journal of Fluid Mechanics},
Turbulent–laminar intermittency, typically in the form of bands and spots, is a ubiquitous feature of the route to turbulence in wall-bounded shear flows. Here we study the idealised shear between stress-free boundaries driven by a sinusoidal body force and demonstrate quantitative agreement between turbulence in this flow and that found in the interior of plane Couette flow – the region excluding the boundary layers. Exploiting the absence of boundary layers, we construct a model flow that… 

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Transition to turbulence in shear flows

  • B. Eckhardt
  • Physics
    Physica A: Statistical Mechanics and its Applications
  • 2018

Oblique laminar-turbulent interfaces in plane shear flows.

It is shown analytically that the corresponding laminar-turbulent interfaces of subcritical flows are always oblique with respect to the mean direction of the flow.

The rise of fully turbulent flow

A bifurcation scenario is uncovered that explains the transformation to fully turbulent pipe flow and the front dynamics of the different states encountered in the process and is bridged between understanding of the onset of turbulence and fully turbulent flows.

Scale invariance at the onset of turbulence in Couette flow.

It is found that turbulence becomes sustained at a distinct critical point once the spatial proliferation outweighs the inherent decaying process and scale invariance at the onset of turbulence is demonstrated.

Distinct large-scale turbulent-laminar states in transitional pipe flow

This work has carried out extensive numerical computations in pipes of variable lengths up to 125 diameters to investigate the nature of transitional turbulence in pipe flow and shows the existence of three fundamentally different turbulent states separated by two distinct Reynolds numbers.

Evolution of turbulent spots in a parallel shear flow.

The evolution of turbulent spots in a parallel shear flow is studied by means of full three-dimensional numerical simulations and it is found that growth of the spots seems to be intimately connected to the large scale outside flow.

The Onset of Turbulence in Pipe Flow

It is shown that in pipes, turbulence that is transient at low Reynolds numbers becomes sustained at a distinct critical point and is intrinsic to the nature of fluid turbulence.

Laminar-turbulent patterning in wall-bounded shear flows: a Galerkin model

On its way to turbulence, plane Couette flow–the flow between counter-translating parallel plates–displays a puzzling steady oblique laminar-turbulent pattern. We approach this problem via Galerkin

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Turbulent-laminar banded patterns in plane Poiseuille flow are studied via direct numerical simulations in a tilted and translating computational domain using a parallel version of the pseudospectral

Long-wavelength modulation of turbulent shear flows