A large scale interface multi-fluid model for simulating multiphase flows

The scope of the Eulerian Multiphase (EMP) model in STAR-CCM+ is extended to simulate multi-scale two-phase flows using Large Scale Interface (LSI) model. The LSI model provides a criteria based on local phase-distribution to distinguish between regimes characterized by small and large scale interfaces. An appropriate closure for conserved variable is specified for each regime, weighted sum of which forms the closure for the interaction between the phases. The LSI model also allows to model surface tension effects in the vicinity of large scale interfaces as well. The large scale interface is treated as a moving wall using a turbulence damping procedure near the interface. This extended multifluid methodology implemented in STAR-CCM+® Software is validated using several standard two-phase flow problems.