Like emulsions, pastes and many other forms of soft condensed matter, aqueous foams present slow mechanical relaxations when subjected to a stress too small to induce any plastic flow. To identify the physical origin of this viscoelastic behaviour, we have simulated how dry disordered coarsening 2D foams respond to a small applied stress. We show that the mechanism of long time relaxation is driven by coarsening induced rearrangements of small bubble clusters. These findings are in full agreement with a scaling law previously derived from experimental creep data for 3D foams. Moreover, we find that the temporal statistics of coarsening induced bubble rearrangements are described by a Poisson process.
@article{arxiv.cond-mat/0512100,
title = {Slow viscoelastic relaxation and aging in aqueous foam},
author = {S. Vincent-Bonnieu and R. Höhler and S. Cohen-Addad},
journal= {arXiv preprint arXiv:cond-mat/0512100},
year = {2016}
}