Visualization of Bubble Collapse near the Wall Under Vibrating and Heating Wall Boundaries
The single bubble collapsing near a wall under complicated wall boundaries was comprehensively investigated using spark-induced cavitation method.Visualization on the collapse behavior of bubbles near different types of vibrating walls and walls with different temperatures reveal that wall vibration promotes bubble collapse,resulting in a faster collapse process and a larger volume change.The effects of different types of walls on the process of bubble collapse differ,columnar walls compared to spherical walls would cause the shape of the bubble near the wall to be more irregular,the collapse shows an overall collapse trend,and an irregular cloud of bubbles will form during the rebound stage.Furthermore,heating the wall interface leads the near-wall collapse which plainly tends to the wall surface and is followed by recurred cavitation,delivering substantial damage to the wall interface.