File Name : movie_contactforces_lowdriving.mp4

Caption : simulation movie of the time-evolution of contact networks during stick-slip flow at low driving force. the circles denote bubble centres, and contact lines, which are shown only when bubble overlaps exceed 12% of the sum of the radii, are coloured according to the extent of overlap. contacts stop changing when bubbles get trapped within a dense network (for example, at time 0.25 - 0.35), and tend to persist close to walls as the flow approaches a jammed state. 

File Name : movie_contactforces_highdriving.mp4

Caption : simulation movie showing the contact networks evolving over time during a steady flow at high driving force. when compared to the movie for stick-slip flow, the contacts are seen to be short-lived due to the fact that kinetic energy dominates over the elastic energy of attraction in the contacts,. this is especially clear near the walls, and also in the steady advection of networks with the flow.

File Name : movie_motion_energy_lowdriving.mp4

Caption : simulation movie of the flowing foam in the stick-slip regime at low driving, with the lower plot showing the simultaneous evolution of total elastic energy. the velocity vector of each bubble is shown as a black line. the intermittent, disordered behaviour of the flow is clearly evident: there are times when the velocity vectors form swirls or end up perpendicular to the direction of flow. these non-uniform motions are accompanied by a slow rise in the elastic energy.

File Name : movie_motion_energy_highdriving.mp4

Caption : simulation movie of a steadily flowing foam at high drive, where in contrast to the stick-slip case, the flow is collective and most velocity vectors point in the direction of the pressure gradient. the corresponding elastic energy shows fluctuations on a smaller time scale compared to the stick-slip regime.