Dynamics of an air bubble induced by an adjacent oscillating bubble

This study is concerned with the collapse of an air bubble induced by its adjacent oscillating bubble, including the splitting of the air bubble and the subsequent transitions of the two split sub-bubbles from singly-connected to doubly-connected. The numerical modeling is based on the potential flow theory coupled with the boundary integral method. A two-vortex-rings model is put forward to further simulate the interaction between two toroidal bubbles and a singly-connected one, which is rarely seen in previous studies. To validate the numerical model, experiments are carried out for the dynamics of an air bubble induced by a spark generated bubble captured by a high speed camera. Our numerical results agree qualitatively with the experimental data. It is found that the strength parameter ε of the oscillating bubble greatly affects the jet velocity of air bubble and the length ratio l′ of air bubble determines its collapsing pattern.