CFD-DEM mixing of rod-like and spherical particles in fluidized beds

Abstract

Understanding the behavior of particle mixing in fluidized beds is crucial for enhancing process design. This article focuses on investigating the effect of key parameters, such as volume fraction of spherical particles, length of rod-like particles, and aspect ratio of rod-like particles, on the mixing of binary mixtures containing spherical and rod-like particles. The study employs a computational approach which couples the computational fluid dynamics and discrete element method (CFD-DEM) to explore mixing behavior of particles. Non-spherical particles are modeled using the multi-sphere method. A combination of qualitative and quantitative approaches is employed to assess the mixing performance, including visual examination of the fluidized bed and calculation of the subdomain-based mixing index. It was shown that an increase in rod-like particle length, aspect ratio, and volume fraction of rod-like particles weaken the mixing. Furthermore, the quality of mixing is directly influenced by bubble size and particle granular temperature. This study offers valuable insights into the mixing behavior of rod-like and spherical particles, contributing to the design and optimization of binary fluidization processes.