Experimental and CFD-PBM Study on Fluidization Behavior of Fine Cohesive Powder in a Pulsed Fluidized Bed

This paper examines the fluidization characteristic of fine cohesive powders within a pulsed fluidized bed, utilizing both experimental and numerical methodologies. A population balance model, integrated with the Eulerian–Eulerian framework (CFD-PBM), has been developed to effectively model the behavior of fine cohesive powders by incorporating cohesive interaction forces. The effects of continuous, on–off pulsed, and mixed airflows were thoroughly investigated. The findings reveal that an increase in pulse frequency to 5 Hz, both the mean particle diameter and the changes in bed height decreased. Furthermore, the particle size distribution and fluidization behavior exhibited greater uniformity. Notably, the agglomerates size diminished by 21.4% to 43% as the frequency increased from 0.033 to 5 Hz. Under mixed airflow conditions, the reduction ranged from 31% to 43.5%. The CFD-PBM results indicate that the fluidization quality greatly enhanced at very low frequencies with mixed airflow, attributed to a more uniform particle size distribution.