Development and implementation of a Direct Surface Description method for free surface flows in OpenFOAM

The solution procedure for two phases in OpenFOAM suffers from unphysical velocity oscillations at the free surface between phases. It is likely that this problem also exists other two-phase Computational Fluid Dynamics (CFD) codes. We aim to solve by imposing boundary conditions directly on surface. have taken first step towards a new method addressing water phase alone. modelling based merging concepts existing methods: (1) A single-phase and (2) used OpenFOAM. underlying motivation enable more accurate estimation of wave induced load distributions crest impacts offshore structures. This foremost requires an prediction kinematics near present with surface, thereby name: Direct Surface Description (DSD). Additionally it time isoAdvector algorithm combined single method. implementation made OpenFOAM, but may relevant codes as well. First still level simulation presented illustrate behaviour solvers validate DSD second test case moderately steep stream function intermediate depth. validated compared methods OpenFOAM: interFoam interIsoFoam. detailed comparison elevations profiles. followed convergence study including height, shift. influence Courant–Friedrichs–Lewy (CFL) number studied. demonstrates accurately predicts elevation fields without undulations or oscillatory fields. underlines increased accuracy Finally, 2D 3D showcase breaking waves are show capable simulating complex realistic cases.