Effect of contact force modeling parameters on the system hydrodynamics of spouted bed using CFD-DEM simulation and 2k factorial experimental design

Abstract

In this study, the effects of contact force modeling parameters, which included the particle–particle friction coefficient (A), spring constant (B), ratio of the tangential spring constant to normal spring constant (C), normal restitution coefficient (D), and tangential restitution coefficient (E) presenting in the linear spring-dashpot contact model on the hydrodynamics profile of spouted bed reactor, were investigated via computational fluid dynamics coupled with discrete element method (CFD-DEM) using Multiphase Flow with Interphase eXchange (MFIX). First, the base case simulation was validated with the experimental data. Next, the 2k factorial experimental design and an analysis of variance (ANOVA) were conducted to identify the significant main and interaction contact force modeling parameters. Four response variables were observed: the translation kinetic energy of particles, the rotational kinetic energy of particles, the bed expansion, and the standard deviation of pressure drop. Based on these results, the particle–particle friction coefficient, spring constant, and normal restitution coefficient were the major contact force modeling parameters that affected the system hydrodynamics in the spouted bed system. In addition, the effects of main and interaction contact force modeling parameters were summarized, which enhanced our knowledge of the modeling parameters on system hydrodynamics. Contact force modeling parameters must be carefully selected when simulating the spouted bed reactor or related gas-solid multiphase flow process, such as fluidized bed reactor.