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arXiv · 2308.06001

Global stability of Oldroyd-B fluids in plane Couette flow

Joshua Binns·Andrew Wynn
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Abstract

We prove conditions for global nonlinear stability of Oldroyd-B viscoelatic fluid flows in the Couette shear flow geometry. Global stability is inferred by analysing a new functional, called a perturbation entropy, to quantify the magnitude of the polymer perturbations from their steady-state values. The conditions for global stability extend, in a physically natural manner, classical results on global stability of Newtonian Couette flow.

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Joshua Binns, Andrew Wynn. 2023-08-11. Global stability of Oldroyd-B fluids in plane Couette flow. https://arxiv.org/abs/2308.06001

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