Super-quadric CFD-DEM simulation of chip-like particles flow in a fluidized bed

Abstract

Chip-like particles may be practised in fluidized beds in some emerging industries, but its fluidization is not well understood. In this work, the computational fluid dynamics-discrete element method (CFD-DEM) is extended to integrate with a super-quadric model to study the fluidization behaviours of chip-like particles in a three-dimensional bubbling fluidized bed (BFB). After model validation, the typical fluidization behaviours of chip-like particles in the BFB are described in terms of bubble dynamics, pressure signals, particle orientation, particle mixing, and particle dispersion. Particularly, the ordered arrangement of chip-like particles appears at the near-wall region while random arrangement occurs in other regions. The effects of superficial gas velocity and aspect ratio on the mixing and dispersion characteristics of chip-like particles are discussed. The results show that increasing aspect ratio induces a higher mean pressure drop and promotes the initial mixing state. Particle dispersion coefficients range from 10-3 m2/s to 10-2 m2/s, whose vertical component is one order of magnitude larger than the horizontal components. Larger aspect ratios and superficial gas velocities lead to larger particle dispersion coefficients. The fundamental study sheds light on the design and optimization of fluidized beds of chip-like particles including solar panel waste recycling.