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arXiv · 2005.12755

Implementation note on a minimal hybrid lubrication/granular dynamics model for dense suspensions

Zhouyang Ge·Luca Brandt
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Abstract

We describe and summarize a class of minimal numerical models emerged from recent development of simulation methods for dense particle suspensions in overdamped linear flows. The main ingredients include (i) a frame-invariant, short-range lubrication model for spherical particles, and (ii) a soft-core, stick/slide frictional contact model activated when particles overlap. We implement a version of the model using a modified velocity-Verlet algorithm that explicitly solves the $N$-body dynamical system in $\mathcal{O}(cN)$ operations, where $c$ is a kernel constant depending on the cutoff of particle interactions. The implementation is validated against literature results on jamming transition and shear thickening suspensions from 40% to 64% volume fractions. Potential strategies to extend the present methodology to non-spherical particles are also suggested for very concentrated suspensions.

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Zhouyang Ge, Luca Brandt. 2020-05-24. Implementation note on a minimal hybrid lubrication/granular dynamics model for dense suspensions. https://arxiv.org/abs/2005.12755

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