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arXiv · 1610.07492

The surface tells it all: Relationship between volume and surface fraction of liquid dispersions

Emilie Forel·Emmanuelle Rio·Maxime Schneider·Sebastien Beguin·Denis Weaire·Stefan Hutzler·Wiebke Drenckhan
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Abstract

The properties of liquid dispersions, such as foams or emulsions, depend strongly on the volume fraction $\phi$ of the continuous phase. Concentrating on the example of foams, we show experimentally and theoretically that $\phi$ may be related to the fraction $\phi_s$ of the surface at a wall which is wetted by the continuous phase - given an expression for the interfacial energy or osmotic pressure of the bulk system. Since the surface fraction $\phi_s$ can be readly determined from optical measurement and since there are good general approximations available for interfacial energy and osmotic pressure we thus arrive at an advantageous method of estimating $\phi$. The same relationship between $\phi$ and $\phi_s$ is also expected to provide a good approximation of the fraction of the bubble or drop surface which is wetted by the continuous phase. This is a parameter of great importance for the rheology and ageing of liquid dispersions.

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Emilie Forel, Emmanuelle Rio, Maxime Schneider, Sebastien Beguin, Denis Weaire, Stefan Hutzler, Wiebke Drenckhan. 2016-10-24. The surface tells it all: Relationship between volume and surface fraction of liquid dispersions. https://doi.org/10.1039/c6sm01451h

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