Experimental and numerical investigation of liquid–solid binary fluidized beds: Radioactive particle tracking technique and dense discrete phase model simulations

Abstract

Liquid–solid binary fluidized beds are widely used in many industries. However, the flow behavior of such beds is not well understood due to the lack of accurate experimental and numerical data. In the current study, the behavior of monodisperse and binary liquid–solid fluidized beds of the same density but different sizes is investigated using radioactive particle tracking (RPT) technique and a dense discrete phase model (DDPM). Experiments and simulations are performed in monodisperse fluidized beds containing two different sizes of glass beads (0.6 and 1mm) and a binary fluidized bed of the same particles for various bed compositions. The results show that both RPT and DDPM can predict the mixing and segregation pattern in liquid–solid binary fluidized beds. The mean velocity predictions of DDPM are in good agreement with the experimental findings for both monodisperse and binary fluidized beds. However, the axial root mean square velocity predictions are only reasonable for bigger particles. Particle–particle interactions are found to be critical for predicting the flow behavior of solids in liquid–solid binary fluidized beds.