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arXiv · 1906.03068

Fully developed and transient concentration profiles of particulate suspensions sheared in a cylindrical Couette

Mohammad Sarabian·Mohammadhossein Firouznia·Bloen Metzger·Sarah Hormozi
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Abstract

We experimentally investigate particle migration in a non-Brownian suspension sheared in a Taylor-Couette configuration and in the limit of vanishing Reynolds number. Highly resolved index-matching techniques are used to measure the local particulate volume fraction. In this wide-gap Taylor-Couette configuration, we find that for a large range of bulk volume fraction, $ϕ_b \in [20\% - 50\%]$, the fully developed concentration profiles are well predicted by the suspension balance model of Nott \& Brady (J. Fluid Mech., vol. 275, 1994, pp. 157-199). Moreover, we provide systematic measurements of the migration strain scale and of the migration amplitude which highlight the limits of the suspension balance model predictions.

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Mohammad Sarabian, Mohammadhossein Firouznia, Bloen Metzger, Sarah Hormozi. 2019-06-02. Fully developed and transient concentration profiles of particulate suspensions sheared in a cylindrical Couette. https://doi.org/10.1017/jfm.2018.982

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