3D CFD simulation of wet rough particles hydrodynamics in a pulsed fluidized bed using kinetic theory of rough spheres model

Abstract

In the framework of kinetic theory of rough spheres (KTRS) model, a dynamic coefficient of restitution model is introduced to describe the collision behavior between wet rough particles in liquid. Based on the two-fluid model (TFM) combining kinetic theory of rough spheres, numerical simulations are conducted on the flow characteristic of rough particles and liquid in a pulsed fluidized bed. The simulation results are firstly validated against experimental data reported by Ehsani et al. Subsequently, the effects of pulsation flow on liquid–solid two-phase flow, particle collision and particle rotation behavior are studied. The results indicate that resonance fluidization occurs at a frequency of 1 Hz, which is approached to the natural frequency of the bed. Furthermore, the particle volume fraction increases with the pulsation amplitude at this frequency. Conversely, at a frequency of 36 Hz, the volume fraction exhibits the opposite trend with the pulsation amplitude. The interstitial fluid increases the dissipation of kinetic energy in particle collision, though its effect is much smaller than that caused by particle rotation.