2D unsteady motion and deformation of a gaseous bubble in a vibrating liquid at zero gravity

Numerical investigation of a bubble immersed in a liquid of different densi ty in a container subject to translational oscillations in weightlessness c onditions shows the following scenario where the bubble, initially located at the container center, starts to move to the container wall due to an att raction mechanism having nonviscous origin. This motion is accompanied by s mall-amplitude oscillations with the frequency equal to the forcing frequen cy and by ei en-oscillations with long period excited by the initial accele ration. These eigen-oscillations are gradually damped. Simultaneously, the deformation of the bubble shape averaged over the external forcing period o ccurs. The bubble is flattened in the direction of vibration axis. An inter esting result is the deceleration of the bubble motion when it approaches t he wall and stops without touching the wall, such that a final state is rea ched where the bubble centroid remains nearly quiescent (performing small o scillations around this final mean position). Numerical results on the ecce ntricity of the inclusion average-shape obtained under assumption that the inclusion cross-section is an ellipse are compared with the results of anal ytical investigation for the case of a cylindrical container of large radiu s. Good agreement is found for a small-size inclusion.