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arXiv · 1503.01701

Low-dimensional representations of exact coherent states of the Navier-Stokes equations from the resolvent model of wall turbulence

Ati S. Sharma·Rashad Moarref·Beverley J. McKeon·Jae Sung Park·Michael D. Graham·Ashley P. Willis
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Abstract

We report that many exact invariant solutions of the Navier-Stokes equations for both pipe and channel flows are well represented by just few modes of the model of McKeon & Sharma J. Fl. Mech. 658, 356 (2010). This model provides modes that act as a basis to decompose the velocity field, ordered by their amplitude of response to forcing arising from the interaction between scales. The model was originally derived from the Navier-Stokes equations to represent turbulent flows and has been used to explain coherent structure and to predict turbulent statistics. This establishes a surprising new link between the two distinct approaches to understanding turbulence.

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Ati S. Sharma, Rashad Moarref, Beverley J. McKeon, Jae Sung Park, Michael D. Graham, Ashley P. Willis. 2015-03-05. Low-dimensional representations of exact coherent states of the Navier-Stokes equations from the resolvent model of wall turbulence. https://doi.org/10.1103/physreve.93.021102

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