Interaction of a rigid buoyant sphere and a deforming bubble with a vortex ring: The role of deformability

Abstract

Bubbly turbulent flows involve complex interactions between the water and the bubbles in which bubble deformation is known to play an important role. We experimentally investigate an idealization, namely, the interaction of a deforming air bubble and a rigid buoyant particle (non-deforming bubble) with a single vortex ring. On the bubble/particle dynamics side, after capture by the low-pressure vortex core, the bubble undergoes large azimuthal expansion within the ring, unlike the particle. This difference in the shape of the bubble compared to the particle, within the ring, leads to distinct differences in the ring time evolution, which brings us insight into the role of deformability in these interactions.