Improvements of LS-DYNA ICFD’s two-phase level-set solver

Numerical simulation of two-phase flows with interface capturing consists in solving a single set of Navier-Stokes equations with variable material properties. Here, we use the level set method for interface capturing [1]. That gives a simple representation of the interface – the level-set scalar field is continuous and allows easy access to geometrical properties at interfaces. That function evolves in time as it is transported by the flow velocity. As the velocity is not uniform in general, the level-set function may need be reinitialized while maintaining the position of interfaces. Numerical methods that are deployed to solve those problems must be chosen meticulously. Depending on the type of flow, advanced numerical techniques must be used to avoid unphysical motion of interfaces. Combinations of numerical methods have been tested on several benchmark tests.