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arXiv · 2204.03317

Rheology and structure of a suspension of deformable particles in plane Poiseuille flow

Vassanti Audemar·Thomas Podgorski·Gwennou Coupier
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Abstract

We present an experimental study of the rheology and structure of a confined suspension of deformable particles flowing in a quasi-two-dimensional Poiseuille flow. Thanks to a precise microfluidic viscosimetry technique combined with measurements of concentration profiles, our study provides the first experimental confirmation {with three-dimensional particles} of a strong relationship between structuring effects and rheology, previously only reported in numerical simulations of purely two-dimensional systems. In conditions where strong structuring effects take place due to confinement, the evolution of the effective viscosity with particle concentration (here, red blood cells) shows a remarkable succession of ranges of rapid growth and plateaus that are associated to qualitative transitions in the structure of the suspension.

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Vassanti Audemar, Thomas Podgorski, Gwennou Coupier. 2022-04-07. Rheology and structure of a suspension of deformable particles in plane Poiseuille flow. https://doi.org/10.1063/5.0087378

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