A level-set aided single-phase model for the numerical simulation of free-surface flow on unstructured meshes

Abstract

A new single-phase scheme for the numerical simulation of free-surface problems on 3-D unstructured meshes is presented. The flow field is obtained from the discrete solution of the incompressible Navier-Stokes equations, whereas a conservative level-set method is employed to capture fluid interfaces on an Eulerian approach. The scheme is based on a novel treatment of the interface for the deactivation of the light phase, allowing an optimization of the classic two-phase model for the cases in which the influence of the lighter phase is negligible. The deactivation is performed by directly imposing the appropriate pressure at the surface boundary, and, unlike similar approaches, without the need to treat near-interface velocities. The method is validated against various analytical and experimental references, demonstrating its potential on both hexahedral and unstructured meshes. Moreover, it shows higher numerical stability in comparison to two-phase solvers, as well as significant advantages in terms of computational performance.