Andrew Belmonte

Reactive Hydrodynamics and Interfacial Instabilities of Micellar Systems

While many fluid instabilities involving free surfaces are governed by interfacial forces - the classic example being surface tension - real materials often have surface forces produced by physical processes not present in the bulk. A striking example of this is a viscoelastic micellar fluid, in which the long tubelike aggregates form at low concentrations due to the presence of an organic salt/cosurfactant, without which the micelles are spherical and the fluid is completely Newtonian. I will present some of our recent experimental observations and modeling of the instabilities occurring when two such Newtonian fluids react to produce a fragile elastic micellar material, either during impact splashes or viscous fingering.