Jetting behavior induced by bubble bursting at the surface of particle suspensions

The bursting of surface bubbles can produce jet droplets and thus mediates the mass transfer across liquid–gas interfaces, which is ubiquitous over a wide range of natural and industrial processes. Though the bubble bursting jetting behavior in pure liquids has been well documented, how the widely existing particulates in liquids affect jet dynamics remains unclear. Here, we experimentally investigate the jet dynamics induced by bubble bursting at the suspension surfaces of submicrometer and micrometer particles with a mass concentration up to 200 g/L. We find that the submicrometer particles in liquids make the jet droplets faster and smaller, which are attributed to the influence of the particles on the viscosity and surface tension of the liquid phase. In contrast, in micrometer particle suspensions, the jet droplets become slower and larger and finally are completely suppressed as the particle concentration increases. By analyzing the influence of particles on the cavity collapse time, we deduce that the micrometer particles modify the jet dynamics by introducing extra surface effects of Marangoni stress or surface elasticity, as micrometer particles are easier to be collected to the bubble surface than submicrometer particles. These results promote our understanding of bubble bursting jetting in complex liquid systems and imply the multiscale hydrodynamic interaction between the particle of different scales and bursting bubbles, which deserves further studies.