An accurate von Neumann's law for three-dimensional foams
S Hilgenfeldt1, A M Kraynik, S A Koehler
1Division of Engineering and Appled Sciences, Harvard University, Cambridge, MA 02138, USA. sascha@tn.utwente.nl
Abstract:
The diffusive coarsening of 2D soap froths is governed by von Neumann's law. A statistical version of this law for dry 3D foams has long been conjectured. A new derivation, based on a theorem by Minkowski, yields an explicit analytical von Neumann's law in 3D which is in very good agreement with detailed simulations and experiments. The average growth rate of a bubble with F faces is shown to be proportional to F1/2 for large F, in contrast to the conjectured linear dependence. Accounting for foam disorder in the model further improves the agreement with data.
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