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arXiv · 2601.01907

Dense granular rheology from fluctuations

Benjamin M. Alessio·Matthew R. Edwards·Ching-Yao Lai
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Abstract

A unifying framework to describe dense flows of dry, deformable grains is proposed. Perturbative analysis of a granular temperature equation describing flows with contact stresses, supported by the recovery of the nonlocal granular fluidity equation, is used to derive an expression for a recently postulated critical exponent. Direct numerical simulation justifies models for the unclosed terms that provide a material-dependent estimate. Non-universality of the velocity and strain rate distributions, arising from competition between production and diffusion, rationalizes model shortcomings.

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Benjamin M. Alessio, Matthew R. Edwards, Ching-Yao Lai. 2026-01-05. Dense granular rheology from fluctuations. https://arxiv.org/abs/2601.01907

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