(349e) 2D Modeling of Foam Flow Using an Interface Tracking Method for Analysing Its Stress-Strain Behavior

Bulk foam is defined as an â??agglomeration of gas bubbles separated from each other by thin liquid filmsâ?.^[1] To simulate the flow of such a system, it is required to solve Navier-Stokes equations coupled with appropriate interface boundary conditions. Amongst many available methods, the level set method makes use of a function indicating the presence of gas or liquid or interface. In this study, we invoke this strategy to model bubble flow in 2D, whilst disregarding the effects of varying interface thicknesses. One of the key motivations behind attempting such simulations, is realization of the stress-strain behavior of the foam at microscales where surface tension forces are dominant. Various models of the shear stress versus strain rate are tested and it is determined whether they are statistically different. Moreover a thin layer of foam is observed through diascopic light in a confocal microscope, and the interface distributions and their evolution are extracted from the images and then nonlinearly regressed against the model to obtain effective viscosity values to inform the underlying constitutive behavior.

 [1] Rossen, W.R. 1996. Foams in Enhanced Oil Recovery. Foamsâ??Theory, Measurement, and Applications, R.K. Prudâ??homme and S.A. Khan ed., 413-464. New York: Marcel Dekker Inc.