Modelling the Microstructure and Stress in Dense Suspensions Under Inhomogeneous Flow

Jurriaan J. J. Gillissen; Christopher Ness

doi:10.1103/physrevlett.125.184503

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arXiv · 2009.14548

Modelling the Microstructure and Stress in Dense Suspensions Under Inhomogeneous Flow

Jurriaan J. J. Gillissen·Christopher Ness

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Abstract

Under inhomogeneous flow, dense suspensions exhibit complex behaviour that violates the conventional homogenous rheology. Specifically, one finds flowing regions with a macroscopic friction coefficient below the yielding criterion, and volume fraction above the jamming criterion. We demonstrate the underlying physics by incorporating shear rate fluctuations into a recently proposed tensor model for the microstructure and stress, and applying the model to an inhomogeneous flow problem. The model predictions agree qualitatively with particle-based simulations.

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Jurriaan J. J. Gillissen, Christopher Ness. 2020-09-30. Modelling the Microstructure and Stress in Dense Suspensions Under Inhomogeneous Flow. https://doi.org/10.1103/physrevlett.125.184503

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