(210c) Towards Accurate Modeling of Vibration in CFD-DEM Simulations of Vibrated Gas-Fluidized Beds

Recent studies have demonstrated that vibration of gas-fluidized beds can produce structured flow dynamics in granular particles, such as structured bubbling, surface waves and convection cells. Computer fluid dynamics (CFD) simulation of these flows has been key to identifying mechanisms underlying these structured flow phenomena. Simulation of vibration of granular particles using the discrete element method (DEM) can be conducted via vibrating the bottom plate. Incorporating this technique with CFD for modeling gas flow in a vibrated gas-fluidized bed is non-trivial because vibrating the entire CFD grid would be computationally expensive. Existing CFD-DEM simulation works model vibration by either oscillating the gravity or moving a bottom plate made by glued particles. Here, we explore multiple methods for modeling vibrated gas-fluidized beds using CFD-DEM simulations and quantify their accuracy based on direct comparison of simulation of structured granular flows. Importantly, we proposed methods to model vibration by moving a gas-penetrable stl geometry in the bottom and imposing a tangential velocity on the sidewalls. Such methods can model the vibration of the whole bed and are the most accurate for the simulation of vibrated fluidized beds so far.