Bubbles in acoustic fields

In these studies, we were interested in the acoustical response of microbubbles covered with particles. The bubbles are around 100 um diameter and the particles between 1-10 um.

We first looked at the shape oscillations of the bubbles and identified a synchronization mechanism between different modes of deformation. This effect leads to greater local deformation of the interface and ultimately can trigger the desorption of particles in specific locations [6].

In a second study, we tried to look precisely at the dynamic organization of the particles at the interface for gentle oscillations. We discovered the formation of a network of strings at the surface for sufficiently low coverage. It results from a subtle combination of capillary interactions (statics but also due to inertial deformation) and hydrodynamics interactions (streaming around the particles). We were able to reproduce the experimental results with numerical simulations.