Plastic deformation in a flowing foam: measurement and prediction

Philippe Marmottant (1) , Christophe Raufaste (1) , François Graner (1)

1 LSP - Laboratoire de Spectrométrie Physique

The plastic flow of a foam results from bubble rearrangements. We study their occurrence in experiments where a foam is forced to flow in 2D: around an obstacle, through a narrow hole, or sheared between rotating disks. We describe their orientation and frequency using a topological tensor which links them with macroscopic plasticity. We then suggest a phenomenological equation to predict the plastic strain rate: its orientation is determined from the foam's local elastic deformation and its rate is determined from the foam's local elongation rate. We obtain a good agreement with statistical measurements. This helps describing the foam as a continuous medium with fluid, elastic and plastic properties, which is the goal of the companion paper (Graner et al., preprint)

Domaines: Matière Molle [cond-mat.soft]

Philippe Marmottant, Christophe Raufaste, François Graner. Plastic deformation in a flowing foam: measurement and prediction. 2007. ⟨hal-00092006v2⟩