Modeling bubble dynamics in rotating foam stirrer reactors: A computational fluid dynamics approach incorporating gas–solid interactions

Abstract

The rotating foam stirrer reactor (RFSR) employs a donut-shaped porous solid foam stirrer to enhance mass transfer in multiphase systems. However, the complex structure of the foam stirrer presents significant challenges for developing efficient computational models, impeding reactor optimization and scale-up. In this work, we developed a novel bubble breakup and coalescence model based on Liao's framework, incorporating the effects of the rotating porous media. A new bubble breakup mechanism was proposed, accounting for the friction and collisions between bubbles and the struts within the foam stirrer. By integrating this model with a porous media approach, we constructed a simplified three-dimensional computational fluid dynamics model of the RFSR. Simulation results reveal that bubble breakup within the porous medium is primarily driven by gas–solid interactions, leading to enhanced mass transfer. The model accurately predicts gas holdup and bubble size distributions, providing valuable insights for reactor design and scale-up.