An interface-tracking computational infrastructure for compressible multiphase processes*

Numerical simulations with interface tracking in a multiphase medium impact many applications. One such example is a combusting solid involving phase change. In these problems interface tracking is crucial to accurately model and capture the interface physics, for example, discontinuous fields at the interface such as density or normal velocity. We present a mathematically consistent and robust computational approach based on interface tracking for multiphase problems involving phase change. A stabilized finite element method is used to solve the compressible Navier-Stokes equations while accounting for the jump conditions across the interface (derived from conservation laws) by using discontinuous interpolations. Interface is tracked using a combination of mesh motion and mesh modification. Mesh motion is applied until mesh deformation leads to undesirable cells, at which point local mesh modification is used to improve the mesh. All steps are done in parallel on distributed meshes. We will demonstrate our approach for problems with multiple interfaces involving large motions (e.g., multiple droplets or grains). Topological changes in the geometry (of any phase) will be considered in the future.