Non-spherical granular flows down inclined chutes

Abstract

Abstract. In this work, we numerically examine the steady-state granular flow of 3D non-spherical particles down an inclined plane. We use a hybrid CPU/GPU implementation of the discrete element method of nonspherical elongated particles. Thus, a systematic study of the system response is performed varying the particle aspect ratio and the plane inclination. Similarly to the case of spheres, we observe three well-defined regimes: arresting flows, steady uniform flows and accelerating flows. Both steady and dynamic macroscopic fields are derived from microscopic data, by time-averaging and spatial smoothing (coarse-graining), including density, velocity, as well as the kinetic and contact stress tensors. The internal morphology of the flow was quantified exploring the solid fraction profiles and the particle orientation distribution. Furthermore, the system's characteristic time and length scales are investigated in detail. Our aim is to achieve a continuum mechanical description of granular flows composed of non-spherical particles based on the micromechanical details. Thus, to evaluate the influence of particle shape on the constitutive response in granular of those systems. However, to meet the proceeding's page restrictions here we will only discuss the dependence of some terms of the continuum averaged equations on the coarse-graining scale, specifically the case of the kinetic part of the stress tensor.

Rheological response of nonspherical granular flows down an incline

“…Numerically, a chute flow of spherocylinders is modeled using a hybrid GPU-CPU discrete element algorithm (DEM) [42,52]. The aspect ratio of the spherocylinders is defined by ξ = L/d = (l + 2r)/2r, where l is the cylinder length and r is the spheroradius.…”

Self-diffusion of spherocylindrical particles flowing under non-uniform shear rate

“…Specifically, we employ a 3D, hybrid CPU-GPU implementation introduced earlier. 25,26 The modeled particles are shapes composed of a cylinder of length l and diameter d , and two hemispherical ends of diameter d . Thus, the particle's aspect ratio can be defined as ξ = L / d , where L = ( l + d ) is the particle total length.…”