Interfacial Flow and Singularities

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Singularities arise in many areas of physics and have the unique ability to organize dynamics in a large region of phase space. In order to understand these singularities, we must study how nature is able to pass through the singular point. In the laboratory, the breakup of a drop or bubble into pieces is an example of a finite-time singularity. The fluid's topology changes because what began as one mass of fluid, ends up as many individual pieces. Quantities such as the fluid velocity and pressure are becoming very large near the singularity where two masses separate, while the size of the connecting neck region shrinks to zero diameter. The exact manner in which these quantities diverge or shrink depends on the fluid parameters, which define universality classes for the singularities, just as in critical phenomena and thermodynamic phase transitions. We study fluid singularities in a variety of systems including bubbles, droplets, and floating liquid puddles. Our tool of choice is ultra-fast video cameras, although we also use other optical and electrical methods to probe the dynamics.


Coalescence of Bubbles and Drops in an Outer Fluid
J. D. Paulsen, R. Carmigniani, A. Kannan, J. C. Burton, and S. R. Nagel. Nature Comm. 5, 3182 (2014).
Simulations of Coulombic Fission of Charged Inviscid Drops
J. C. Burton and P. Taborek. Physical Review Letters 106, 144501, (2011).