Monte Carlo and MD Modeling of Density Relaxation by Tapping

TL;DR

This study uses Monte Carlo and molecular dynamics simulations to explore how tapping influences density relaxation in granular materials, revealing a critical tap intensity that maximizes packing density through evolving ordered structures.

Contribution

It introduces a combined simulation approach to identify the critical tap intensity and elucidates the relaxation mechanism involving quasi-ordered packing evolution.

Findings

Existence of a critical tap intensity for maximum density

Relaxation driven by upward propagating ordered structures

Density depends on overburden and tap strength

Abstract

The density relaxation phenomenon is modeled using both Monte Carlo and dissipative MD simulations to investigate the effects of regular taps applied to a vessel having a planar floor filled with monodisperse spheres. Results suggest the existence of a critical tap intensity that depends on the mass overburden, which produces a maximum bulk solids fraction. We find that the mechanism responsible for the relaxation phenomenon is evolving quasi-ordered packing structure propagating upwards from the plane floor.