Abstract

Liquid foams consist of gas bubbles and liquid carrying channels called Plateau borders. A foam can be categorised as being dry or wet, depending on how much liquid is contained in the Plateau borders. A dry foam consists of a packing of polyhedral shaped bubbles separated by thin films. In a wet foam, the Plateau borders are more swollen and the bubbles retain a more spherical shape.  In the wet limit, approximating bubbles as soft discs (in 2D) or soft spheres, as done by Durian’s bubble model [1], becomes justified. In this simple and efficient model, bubble motion is determined by a repulsion between overlapping neighbouring bubbles and a viscous drag force. One aspect of foam behaviour that the model has been used to probe is coarsening due to gas diffusion between neighbouring bubbles [2,3]. We will revisit this work, and explore how the model encapsulates the coarsening dynamics of wet foams, both in 2D and 3D, and probe how bubbles rearrange during the process. [1] Durian, D. J., Phys Rev Lett, 1995, 75, 4870 [2] Gardiner, B. et al., Phil. Mag. A, 2000, 80, 981-1000 [3] Khakalo, K et al., Phys. Rev. E, APS , 2018, 98, 012607