Deposition of general ellipsoidal particles

TL;DR

This paper systematically investigates how particle shape and size polydispersity affect the density and anisotropy of granular deposits composed of ellipsoidal particles, revealing shape's significant influence and polydispersity's secondary role.

Contribution

It provides a comprehensive analysis of the macroscopic properties of ellipsoidal particle deposits, highlighting the impact of shape parameters and polydispersity, and introduces an efficient molecular dynamics simulation approach.

Findings

Shape significantly influences deposit properties.

Density peaks for certain non-symmetrical ellipsoids.

Contact forces are vertically aligned with shape deviations.

Abstract

We present a systematic overview of granular deposits composed of ellipsoidal particles with different particle shapes and size polydispersities. We study the density and anisotropy of such deposits as functions of size polydispersity and two shape parameters that fully describe the shape of a general ellipsoid. Our results show that, while shape influences significantly the macroscopic properties of the deposits, polydispersity plays apparently a secondary role. The density attains a maximum for a particular family of non-symmetrical ellipsoids, larger than the density observed for prolate or oblate ellipsoids. As for anisotropy measures, the contact forces show are increasingly preferred along the vertical direction as the shape of the particles deviates for a sphere. The deposits are constructed by means of an efficient molecular dynamics method, where the contact forces are efficiently and accurately computed. The main results are discussed in the light of applications for porous media models and sedimentation processes.