A comprehensive comparison of Two-Fluid Model, Discrete Element Method and experiments for the simulation of single- and multiple-spout fluidized beds

We employ a two-fluid model (TFM) as well as a computational fluid dynamics coupled to discrete ele-ment method (CFD-DEM) approach to study the time averaged hydrodynamics of single-and multiple -spout fluidized beds. Simulations are validated against the experimental data of (van Buijtenen et al., Numerical and experimental study on multiple-spout fluidized beds, Chemical Engineering Science 66 (2011) 2368-2376) with four different interphase drag correlations. The kinetic theory of granular flow used for solving the motion of the solid phase in TFM, includes realistic particle-wall boundary condi-tions for momentum transfer and the flux of pseudo-thermal energy. Frictional stresses in TFM are mod-elled based on a l(I)-rheology. We propose a new ad hoc modification of the l(I)-rheology to account for the effect of rolling friction in TFM. In contrast, in CFD-DEM rolling friction is accounted by an additional torque. Our results show that there is a good agreement between both approaches with respect to time averaged volume fraction, solids velocities, solids fluxes and granular temperature.(c) 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Automated summary

In this study, a two-fluid model (TFM) and a computational fluid dynamics coupled to discrete element method (CFD-DEM) approach are employed to investigate the hydrodynamics of single and multiple-spout fluidized beds. The simulations are validated against experimental data and the results show good agreement between the TFM and CFD-DEM approaches in terms of volume fraction, solids velocities, solids fluxes, and granular temperature.