Internal Avalanches in a Granular Medium

TL;DR

This paper investigates avalanches in a granular medium, demonstrating self-organized criticality and the role of arches in universal behavior through experiments and cellular automata modeling.

Contribution

It introduces a cellular automata model showing how arch formation governs avalanche dynamics and criticality in granular systems.

Findings

Avalanche size distribution follows power-law behavior.

Arch formation influences the critical state.

Model reproduces experimental avalanche signatures.

Abstract

Avalanches of grain displacements can be generated by creating local voids within the interior of a granular material at rest in a bin. Modeling such a two-dimensional granular system by a collection of mono-disperse discs, the system on repeated perturbations, shows all signatures of Self-Organized Criticality. During the propagation of avalanches the competition among grains creates arches and in the critical state a distribution of arches of different sizes is obtained. Using a cellular automata model we demonstrate that the existence of arches determines the universal behaviour of the model system.