78th Annual Meeting of the APS Division of Fluid Dynamics (Nov 23 — 25, 2025)

V046: Fractured Flows: Bursting Bubbles in Dense Suspensions

In contrast to the classical bursting of a bubble in a Newtonian liquid, bubbles in dense suspensions exhibit novel dynamics driven by interfacial instabilities and non-Newtonian rheology. The bursting dynamics of air bubbles in cornstarch suspensions are investigated across a range of mass fractions, revealing distinct bursting regimes: a fracture regime at lower mass fractions and a viscous-dominated circular opening regime at higher mass fractions. The transition to the fracture regime occurs as the thin suspension film dynamically solidifies, evidenced by a visible change in the film interface from shiny to rough. Remarkably, the fractured films exhibit wrinkling instabilities, and the number of fracture fronts decreases with increasing mass fraction, enabling control over the rupture morphology.