気泡の崩壊時における気液界面構造の分子動力学解析

Abstract

In our previous study, the phenomenon that a tiny vapor bubble re-appeared after its first collapse in a molecular scale was observed in a Molecular Dynamics (MD) simulation. In this study, we tried to elucidate the mechanism of the phenomenon in order to further examine whether we can express this phenomenon in continuum mechanics, and we reinvestigated a bubble collapse by molecular dynamics simulation. Here, we compared the liquid-vapor interfacial structure in the non-equilibrium state at a bubble collapse with the liquid-vapor interfacial structure in an equilibrium or a near equilibrium state. As a result, non-equilibrium characteristics were strong at the time of a bubble collapse, and the liquid-vapor interfacial structure was greatly different from that at equilibrium or near equilibrium condition. In addition, we found that the rebound of a bubble in the non-equilibrium state is the cause of becoming strong repulsive force between molecules in the liquid-vapor interfacial region.