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arXiv · 1310.3935

Macroscopic limit of a one-dimensional model for aging fluids

David Benoit·Claude Le Bris·Tony Lelièvre
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Abstract

We study a one-dimensional equation arising in the multiscale modeling of some non-Newtonian fluids. At a given shear rate, the equation provides the instantaneous mesoscopic response of the fluid, allowing to compute the corresponding stress. In a simple setting, we study the well-posedness of the equation and next the long-time behavior of its solution. In the limit of a response of the fluid much faster than the time variations of the ambient shear rate, we derive some equivalent macroscopic differential equations that relate the shear rate and the stress. Our analytical conclusions are confronted to some numerical experiments. The latter quantitatively confirm our derivations.

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David Benoit, Claude Le Bris, Tony Lelièvre. 2014-04-27. Macroscopic limit of a one-dimensional model for aging fluids. https://arxiv.org/abs/1310.3935

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