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arXiv · 2404.03450

Computational analysis of a contraction rheometer for the grade-two fluid model

Sara Pollock·L. Ridgway Scott
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Abstract

We explore the possibility of simulating the grade-two fluid model in a geometry related to a contraction rheometer, and we provide details on several key aspects of the computation. We show how the results can be used to determine the viscosity $\nu$ from experimental data. We also explore the identifiability of the grade-two parameters $\alpha_1$ and $\alpha_2$ from experimental data. In particular, as the flow rate varies, force data appears to be nearly the same for certain distinct pairs of values $\alpha_1$ and $\alpha_2$; however we determine a regime for $\alpha_1$ and $\alpha_2$ for which the parameters may be identifiable with a contraction rheometer.

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Sara Pollock, L. Ridgway Scott. 2024-04-04. Computational analysis of a contraction rheometer for the grade-two fluid model. https://arxiv.org/abs/2404.03450

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