On the criteria of jet types during a bubble collapse near the tissue-mimicking boundary

The collapse of a cavitation bubble near a tissue membrane generates intense microscopic flows, emits shock wave, and can lead to membrane damage. Experimental works show that the collapse of a cavitation bubble leads to more violent two axial jets flow with decreasing bubble–boundary distance. The critical stand-off distance for the formation of such a jet flow varies largely under different material properties. We investigate the evolution of cavitation induced jet flow experimentally and theoretically comprehensively. A dimensionless impulse is proposed based on image-source model, considering the influence of boundary. A regime map is constructed, revealing a unique law for various materials. The current work may offer insight into the application of cavitation bubbles in biomedical engineering.