High-speed jetting and spray formation from bubble collapse

• Main Authors: O’Shea, Sean J., Karri, Badarinath, Avila, Silvestre Roberto Gonzalez, Loke, Yee Chong, Klaseboer, Evert, Khoo, Boo Cheong, Ohl, Claus-Dieter
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2013
• Online Access: https://hdl.handle.net/10356/95215; http://hdl.handle.net/10220/9229
• Institution: Nanyang Technological University

A method to create impacting jets at the micrometer length scale by means of a collapsing cavitation bubble is presented. A focused shock wave from a lithotripter leads to the nucleation of a cavitation bubble below a hole of 25 μm diameter etched in a silicon plate. The plate is placed at an air-water interface. The expansion and collapse of the bubble leads to two separate jets—an initial slow jet of velocity ∼10 m/s and a later faster jet of velocity ∼50 m/s. The jets subsequently impact coaxially, resulting in a circular sheet of liquid in the plane perpendicular to their axis. The sheet is characterized by a ring of droplets at its rim and breaks up into a spray as the shock pressure is increased. The results demonstrate an approach to create a high-speed jet and fine spray on demand at the micrometer scale.