【論文特集】混相流研究の進展
微小蒸気泡の安定性に関する分子動力学解析
キーワード:
Molecular Dynamics Simulation,
Nanobubbles,
Lennard-Jones Fluid,
Young-Laplace equation,
Phase Equilibrium
2018 年 32 巻 1 号 p. 43-48
詳細
2018 年 32 巻 1 号 p. 43-48
We investigate the vapor bubble stability in liquid argon and water using a molecular dynamics simulation. The Lennard-Jones interparticle interaction potential is used to simulate the interaction forces between molecules. The Stillinger' s cluster criterion is employed to classify the vapor molecules evaporated from the bulk liquid. Using this criterion, the vapor molecules are determined to have no neighboring molecules within a 1.23 to 1.32σ radius, where σ is the interaction radius in the L-J potential. The pressure of vapor and liquid phase can be calculated from the virial equation of sate. The stability of bubble is disscussed applying the Young-Laplace equation. The spherical bubble shape is maintained, when the liquid pressure takes the negative value. The thickness of vapor-liquid interface and the number of molecules across vapor-liquid interface are not proportional to the size of bubbles.
