Numerical Simulation for Generation Mechanism of Ultrafine Bubble by High-Speed Stirring

(Effects of Initial Gas-liquid Volumetric Ratio)

Abstract

In order to clarify mechanism of ultrafine bubble generation by high-speed stirring, mixing process of two-phase flow in the vessel was calculated using lattice Boltzmann method. The process of elongated gas pillars splitting to generate a many small bubbles was confirmed. We proposed the interface length as a new index to quantitatively evaluate the formation of small bubbles. It was found the interface length was the longest when the initial gas-liquid volumetric ratio was 1: 1, and this result qualitatively agreed with the experimental results.