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arXiv · 1704.03567

Universal continuous transition to turbulence in a planar shear flow

Matthew Chantry·Laurette S. Tuckerman·Dwight Barkley
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Abstract

We examine the onset of turbulence in Waleffe flow -- the planar shear flow between stress-free boundaries driven by a sinusoidal body force. By truncating the wall-normal representation to four modes, we are able to simulate system sizes an order of magnitude larger than any previously simulated, and thereby to attack the question of universality for a planar shear flow. We demonstrate that the equilibrium turbulence fraction increases continuously from zero above a critical Reynolds number and that statistics of the turbulent structures exhibit the power-law scalings of the (2+1)-D directed percolation universality class.

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Matthew Chantry, Laurette S. Tuckerman, Dwight Barkley. 2017-08-15. Universal continuous transition to turbulence in a planar shear flow. https://doi.org/10.1017/jfm.2017.405

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