Simulation of Gas-Liquid Flow in an Oscillatory Baffled Reactor Using COMSOL

In recent times, oscillatory baffled reactors have been gaining acceptance for use in various industrial processes due to their appealing mixing and mass transfer characteristics. In addition to the baffles, which are artificially attached, oscillatory baffled reactors produce additional fluid turbulence that is very useful in improving chemical reaction, fermentation, and wastewater treatment processes. This study describes in detail a simulation of the gas-liquid flow inside an Oscillatory Multi-orifice Baffled Reactor (OMOBR), focusing on the hydrodynamic aspects of different oscillation scenarios and baffle spacing as performed using the COMSOL Multiphysics software. The study explains the patterns of flow, bubble size, and pressure drop using oscillatory Reynolds numbers and advanced computational tools. The findings reveal that increased oscillatory Reynolds numbers enhance turbulent flow and bubble size, thus improving the homogeneity of the gas-liquid system. With lower oscillatory Reynolds numbers, the flow becomes smooth, and bubbles are larger and more stable without the violent pulsations typical of a bubble column reactor. However, when the oscillatory Reynolds number increases, the flow induces violent turbulence, and this reduces the bubble diameter and increases the pressure drop. Also, the baffle spacing (l=1.0D) causes comparatively lesser pressure drop with smaller bubble sizes than the other dimensions utilized. These studies bring to light useful information regarding the conditions of oscillation that can allow reaching the optimal parameters and efficiency of an industrial reactor.