Studies of Diffusional Mixing in Rotating Drums via Computer Simulations

TL;DR

This study uses comprehensive 3-D computer simulations to analyze particle diffusion in rotating drums, revealing nonlinear behavior in two-component systems and aligning qualitatively with experimental data.

Contribution

It introduces a parameter-free 3-D simulation model to investigate diffusional mixing, highlighting nonlinear effects in two-component systems.

Findings

Diffusion coefficient for single-component systems matches experimental trends.

Two-component systems show highly nonlinear diffusion dependence on rotation speed.

Flow dynamics involve a competition between axial diffusion and perpendicular flow.

Abstract

Particle diffusion in rotating drums is studied via computer simulations using a full 3-D model which does not involve any arbitrary input parameters. The diffusion coefficient for single-component systems agree qualitatively with previous experimental results. On the other hand, the diffusion coefficient for two-component systems is shown to be a highly nonlinear function of the rotation velocity. It is suggested that this results from a competition between the diffusive motion parallel to, and flowing motion perpendicular to the axis of rotation.