Influence of Internal Phenomena on Gas Bubble Motion.Effects of Transport Phenomena and Mist Formation inside Bubble in the Expanding Phase.

The motion of a single bubble is simulated when the surrounding pressure decreases stepwise. In this simulation, the conservation equations for mass, momentum and energy are solved directly in order to estimate the effect of internal phenomena on bubble motion. At the same time, the mist formation in the gas phase and the diffusions of heat and noncondensable gas in the liquid phase are taken into account. The numerical results for several cases reveal that nondimensional transport coefficients have large effects on the distributions of temperature, concentration of vapor and the mist formation. As the initial radius becomes smaller or depressurization ratio becomes larger, bubble motion is less influenced by mist formation due to the heat penetration through the bubble wall by heat conduction.