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arXiv · 2210.09961

Polymeric diffusive instability leading to elastic turbulence in plane Couette flow

Miguel Beneitez·Jacob Page·Rich R. Kerswell
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Abstract

Elastic turbulence is a chaotic flow state observed in dilute polymer solutions in the absence of inertia. It was discovered experimentally in circular geometries and has long been thought to require a finite amplitude perturbation in parallel flows. Here we demonstrate, within the commonly-used Oldroyd-B and FENE-P models, that a self-sustaining chaotic state can be initiated via a linear instability in a simple inertialess shear flow caused by the presence of small but non-zero diffusivity of the polymer stress. Numerical simulations show that the instability leads to a three-dimensional selfsustaining chaotic state, which we believe is the first reported in a wall-bounded, parallel, inertialess viscoelastic flow.

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Miguel Beneitez, Jacob Page, Rich R. Kerswell. 2022-10-18. Polymeric diffusive instability leading to elastic turbulence in plane Couette flow. https://arxiv.org/abs/2210.09961

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