P15.00004. Flow of Emulsions with Insoluble Surfactant through Porous Media
Presented by: Jake
While our understanding of surfactants’ effect on single-drop dynamics has recently been improving, the general rheology of confined and contaminated emulsions remains less characterized. In particular, complex multiscale behavior results when the drop size is larger than granular interstices. In such cases, the emulsion cannot be treated as a single phase and a droplet-resolved model is required. A pressure-driven, concentrated emulsion flowing through a packed bed of spheres is modeled using a three-dimensional boundary-integral algorithm. The emulsion is initially monodisperse and uniformly coated with surfactant, and subsequently advected using a recently-developed robust algorithm for insoluble surfactant transport, with added options for complex equations of state as well as drop breakup. The ensemble-averaged permeabilities of the drop and continuous phases are studied versus degree of contamination and capillary number, with an emphasis on the effect of surfactant on the droplet-breakup cascade. The possibility of daughter drops having a significantly different surfactant concentration, and therefore capillary number, compared to the original drops results in particularly rich local and global dynamics.
- Jacob R. Gissinger
- Alexander Z Zinchenko* and Robert H Davis