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arXiv · 2110.10976

On variable viscosity and enhanced dissipation

Xian Liao·Christian Zillinger
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Abstract

In this article we consider the 2D Navier-Stokes equations with variable viscosity depending on the vertical position. As our main result we establish linear enhanced dissipation near the non-affine stationary states replacing Couette flow. Moreover it turns out that the shear flow overcompensates for weakening viscosity: decreasing viscosity leads to stronger enhanced dissipation and increasing viscosity leads to weaker dissipation than in the constant viscosity case.

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Xian Liao, Christian Zillinger. 2021-10-21. On variable viscosity and enhanced dissipation. https://arxiv.org/abs/2110.10976

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