Bubble collapse in complex geometries
Fluids and Materials Seminar
4th April 2019, 2:00 pm – 3:00 pm
Main Maths Building, SM3
In this seminar I will give an overview of recent and ongoing work on the collapse of vapour bubbles near solid boundaries. The vapour bubbles I will discuss are made by laser induced cavitation, which creates mm-sized bubbles that go through a cycle of expansion and collapse in about 300 microseconds. If such a bubble is created in an infinite bath of liquid, the bubble remains largely spherical during the expansion and collapse. If the bubble is created near a solid wall, however, the bubble loses its spherical shape and generates a fast jet pointed towards the wall. This phenomenon has been of interest for just over 100 years by now because of the damaging effects of these collapses, known as cavitation erosion. Although the collapse near a single solid wall is well understood, little is known about the behaviour in more complex geometries. I will start with a very basic question: what happens if a bubble collapses in a corner, made of two walls? I will show how analytic predictions can be made for the direction of the collapse in specific corners and how this analysis can be extended to several more complex geometries.
Y. Tagawa and I. R. Peters, “Bubble collapse and jet formation in corner geometries,” Phys. Rev. Fluids 3, 081601 (2018)