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arXiv · 1811.04736

Computing collision stress in assemblies of active spherocylinders: applications of a fast and generic geometric method

Wen Yan·Huan Zhang·Michael J. Shelley
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Abstract

In this work, we provide a solution to the problem of computing collision stress in particle-tracking simulations. First, a formulation for the collision stress between particles is derived as an extension of the virial stress formula to general-shaped particles with uniform or non-uniform density. Second, we describe a collision-resolution algorithm based on geometric constraint minimization which eliminates the stiff pairwise potentials in traditional methods. The method is validated with a comparison to the equation of state of Brownian spherocylinders. Then we demonstrate the application of this method in several emerging problems of soft active matter.

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Wen Yan, Huan Zhang, Michael J. Shelley. 2018-11-12. Computing collision stress in assemblies of active spherocylinders: applications of a fast and generic geometric method. https://doi.org/10.1063/1.5080433

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