Study on heterogeneous gas-solid structure and interparticle collision behavior in a vibrated fluidized bed of Geldart D particles using CFD-DEM simulations

Abstract

The spatiotemporal characteristics of the heterogeneous gas-solid structure and interparticle collisions in fluidized beds of Geldart D particles with and without vibration were comparatively studied by the coupled CFD-DEM simulations. The effects of vibration on the spatiotemporal distributions of particle configuration and particle dynamics were revealed utilizing data visualization and frequency domain analysis. The results show that the input vibration facilitates the formation of square-nosed slugs and improves the uniformity of gas-solid contacts. Moreover, vibration causes fluctuations in static air pressure on the entire bed simultaneously. It is revealed that the introduction of vibration can significantly increase the intensity and uniformity of interparticle collisions, the number of particles involved in collisions, and the total kinetic energy of the bed. The results also show that there exists a positive correlation between average collision number and solid volume fraction while an inverse correlation between granular temperature and solid volume fraction.