液々界面を横切って上昇する気泡運動の三次元数値解析

Abstract

Ternary fluid flows that single bubbles rise across the interface separating two immiscible liquids (liquid-liquid layer) are investigated through three-dimensional numerical analysis based on the moment-of-fluid (MOF) method. In this study, the effect of the viscosity of both liquids on the bubble rise motion and the behavior of the liquid-liquid interface is discussed. From numerical results, it is clearly shown that the viscosity of the liquids has a significant effect on the motion of a single bubble rising through the liquid-liquid layer. When a bubble rises in the lower layer with the low-viscosity, the bubble rise motion shows dynamic behavior, and the behavior of the liquid-liquid interface is complicated. Also, after passing the liquid-liquid interface, the bubble largely trails the lower layer with the low-viscosity fluid. On the other hand, the dynamic behavior of a bubble cannot be seen when a bubble rises through the liquid-liquid interface between high-viscosity fluids. The MOF method allows us to reproduce the dynamic motion of a single bubble rising across a liquid-liquid layer with a ternary fluid interface.