Microscopic Model for Granular Stratification and Segregation

TL;DR

This paper introduces a microscopic lattice model to simulate and analyze the segregation and stratification phenomena in granular mixtures during silo flow, capturing various observed morphologies.

Contribution

It presents a novel microscopic lattice model that incorporates energy dissipation and geometrical asperities to predict granular segregation and stratification.

Findings

Model predicts segregation, stratification, and mixing regions.

Results align with experimental observations.

Phase diagram maps different granular morphologies.

Abstract

We study segregation and stratification of mixtures of grains differing in size, shape and material properties poured in two-dimensional silos using a microscopic lattice model for surface flows of grains. The model incorporates the dissipation of energy in collisions between rolling and static grains and an energy barrier describing the geometrical asperities of the grains. We study the phase diagram of the different morphologies predicted by the model as a function of the two parameters. We find regions of segregation and stratification, in agreement with experimental finding, as well as a region of total mixing.