Flow regime transition and bubble behavior in gas-liquid two-phase impinging jet reactor

Abstract

The gas-liquid flow regimes transition mechanism and bubble behavior in gas-liquid two-phase impinging jet reactor are studied by numerical method. The liquid phase velocity, gas-liquid flow regimes, bubble behavior in the impinging reactor under different gas and liquid velocities are analyzed to explore. The vortex in flow field changes periodically, and the period is 7.5 s. According to the dispersion mode of bubbles in the reactor, the gas-liquid flow regimes can be divided into three regimes: cluster upflow, gradual dispersion and complete dispersion. The critical condition equations of flow regimes transition are established combination of Flow number (Fl) and Froude number (Fr). The distribution range of bubble diameter in the reactor increases with the increase of gas velocity and decreases with the increase of liquid velocity. The turbulent kinetic energy, turbulent dissipation rate and the velocity in the flow field are gradually weakens from the impact center to the radial direction. Based on dimensionless analysis, the mathematical model of bubble Sauter diameter is established to predict bubble Sauter diameter accurately. This research provides a theoretical basis for the amplification and optimization of reactors.