PEPT validated CFD-DEM model of aspherical particle motion in a spouted bed

Computational Fluid Dynamics coupled with Discrete Element Method (CFD-DEM) has been used to model the dynamics of aspherical particles in a spouted bed. CFD-DEM results were rigorously validated against high-resolution, three-dimensional experimental data acquired using Positron Emission Particle Tracking (PEPT). A workflow facilitating the direct, detailed, quantitative comparison of experimental and numerical data, and thus validation of CFD-DEM simulations, was developed. Sensitivity analysis considering a wide range of particle properties and drag correlations was carried out. It was observed that the Young’s modulus, Poisson’s ratio, and restitution coefficient do not have a significant effect on the system’s dynamics across the range of parameters explored, and that Gidaspow’s correlation using equivalent intrinsic particle density is an appropriate choice for modelling drag forces. Analysis shows PEPT-validated CFD-DEM models quantitatively capture key features including particle circulation time, particle velocity and occupancy distributions, and the proportion of residence time in the bulk-bed and freeboard regions, all of which are crucial to understanding mass and heat transfer within the system. Our results also demonstrated that models using simple, spherical particles were – with suitably modified friction and drag models – capable of quantitatively reproducing the dynamics of a range of highly aspherical materials.