title: High-speed jetting and spray formation from bubble collapse.
abstract: 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.
authors.affiliation: NUS Graduate School for Integrative Sciences and Engineering (NGS), Center for Life Sciences, #05-01, 28 Medical Drive, Singapore 117456.
authors.forename: Badarinath
authors.initials: B
authors.lastname: Karri
authors.forename: Silvestre Roberto Gonzalez
authors.initials: SR
authors.lastname: Avila
authors.forename: Yee Chong
authors.initials: YC
authors.lastname: Loke
authors.forename: Sean J
authors.initials: SJ
authors.lastname: O'Shea
authors.forename: Evert
authors.initials: E
authors.lastname: Klaseboer
authors.forename: Boo Cheong
authors.initials: BC
authors.lastname: Khoo
authors.forename: Claus-Dieter
authors.initials: CD
authors.lastname: Ohl