Evaluation of Level Set reinitialization algorithms for phase change simulation on unstructured grids

In this study, we present different numerical methods for the simulation of liquid-vapor phase change (boiling). We use a Level Set formalism to capture the liquid-vapor interface. Such a formalism requires a reinitialization (aka redistancing) step of the Level Set function after advection. This step is critical for phase change simulation as it must neither move the interface nor induce perturbations in the Level Set function profile, otherwise the normal vector to the interface and its curvature, two quantities that are crucial to define respectively the interface velocity due to phase change and the pressure jump at the interface due to surface tension, would be in turn affected by too large numerical errors. Here we present a comparison of different reinitialization algorithms of the Level Set function for boiling simulations, on structured and unstructured grids. These methods are then validated against the analytical case of a static growing bubble with a fixed mass transfer rate. In particular, we observe that at the time corresponding to a doubled bubble radius, the error on the bubble radius decreases with the grid cell size for all presented methods.