Robust computational algorithms for dynamic interface tracking in three dimensions

Front tracking provides sharp resolution of wave fronts through the active tracking of interfaces between distinct materials. A major challenge to this method is to handle changes in the interface topology. We describe two algorithms, implemented in the front tracking code FronTier, to model dynamic changes in three-dimensional interfaces. The two methods can be combined to give a hybrid method that is superior to each individual method. The success of these algorithms is shown by simulations of Rayleigh Taylor instability, which is an interfacial instability driven by an acceleration directed across a material interface. Our numerical results are validated by comparing the numerical computation of the velocity of a single rising bubble with an analytic model for the bubble velocity.