Dynamics of collapsing multi-bubble arrangements

A planar shock front produced in a shock tube provides an instantaneous pressure rise within a water-like gelatin mixture that contains arrangements of millimeter-sized air bubbles. This article studies how bubbles react to this sudden pressure jump and analyzes the complex dynamics and interactions that are involved. Bubble dynamics are captured with a high-speed camera and extracted image sequences for conducted experiments are presented. Experiments include pairs of bubbles of equal and different size in the free field as well as near a solid boundary. For equally sized bubbles in the free field we observe jetting toward each other and coalescence after the second oscillation cycle. Bubbles of different size show a combination of jetting toward and jetting away caused by the out-of-phase oscillation. For a bubble pair aligned normal to a solid boundary we observe that the outer bubble influences the collapse of the inner bubble so that there is no aspherical behavior or jet development. An exemplary experiment with three bubbles in a triangular arrangement next to a solid boundary is presented to highlight the potential for future investigations.     «

A planar shock front produced in a shock tube provides an instantaneous pressure rise within a water-like gelatin mixture that contains arrangements of millimeter-sized air bubbles. This article studies how bubbles react to this sudden pressure jump and analyzes the complex dynamics and interactions that are involved. Bubble dynamics are captured with a high-speed camera and extracted image sequences for conducted experiments are presented. Experiments include pairs of bubbles of equal and d...     »