An experimental study on the dynamics and damage capabilities of a bubble collapsing in the neighborhood of a floating ice cake. (January 2020) - Yuan, G.-Y.
Abstract: We demonstrate dynamics of a bubble collapsing near a floating ice cake and its damage capabilities by virtue of high-speed jet and emitted shockwave, by doing indoor experiments in a water tank in a cold room. An ice cake is made of fresh water in a cryostat, processed and placed in a water tank in a cold room, while the bubble is generated by electric spark at a distance beneath the floating ice cake. Their interaction is observed and recorded by a high-speed camera. A new observation technique is developed to observe the dynamics of bubble and ice simultaneously. The dynamics of the bubble involving bubble jet and shock wave are captured and the damage effects of bubble loads on the ice, including cracks, breakup and movement, are analyzed. It is found that three damage patterns can be generated on the ice according to the damage degree and crack development: crevasse pattern, radial and circumferential cracks pattern and radial cracks pattern. On this basis, the effects of ice thickness and the distance between the bubble and ice are studied and the possible referential ranges of the damage effects of bubble loads with these two parameters are investigated. It can be seen from the experiments that the collapse of the bubble can cause violent damage to the ice.