Viscous froth model applied to the dynamic simulation of bubbles flowing in a channel: three-bubble case

A two-dimensional foam system comprised of three bubbles is studied via simulations with the viscous froth model. Bubbles are arranged in a so-called staircase configuration and move along channel due to imposed driving back pressure. This flowing three-bubble has been previously on basis that it interpolates between simpler structure (a simple lens, which breaks up topological transformations if driven at high pressure) an infinite (which sustains arbitrarily large pressure without breaking). Depending bubble size relative size, different solution branches for were found: certain terminate (as lens) others reach staircase) geometrically invariant migrating state. The methodology used was, however, purely steady state one, hence did not interrogate stability various branches, nor role imposing pressures upon transformation type. To address this, unsteady realized here. Stable exist comparatively low pressures. For sufficiently pressures, occur, albeit now influencing