An improve model for predicting bed density of the air dense medium fluidized bed based on Geldart B particles

Abstract

The spatiotemporal distribution characteristics of the bed density formed by gas–solid two-phase flow in an air dense medium fluidized bed (ADMFB) played a crucial role in heat transfer, mass transfer, and mixing-separation behavior. To address the issue of underestimation of density prediction in the bottom region by existing bed density correlations, this study established a density spatial distribution calculation model based on local bubble coalescence and breakage behavior. The model coefficients for different regions were corrected using experimental data, compensating for the inadequacies of the existing bed density correlations. The overall average standard deviation of the new model was controlled within ±7.69 %, showing good agreement with the data from existing literature. This study provided a more accurate and reliable theoretical foundation for predicting the spatiotemporal distribution of bed density in gas-solids fluidized beds.