An accurate three-dimensional (3D) Numerical Wave Tank solving fully nonlinear potential flow theory is developed and validated for modeling wave propagation up to overturning over arbitrary bottom topography. The model combines a higher-order 3D-BEM and a Mixed-Eulerian-Lagrangian time updating of the free surface, based on explicit secondorder Taylor series expansions, with adaptive time steps. The spatial discretization is third-order and imposes continuity of the inter-element slopes. Diseretized boundary conditions at intersections between domain boundary sections (corner/edges) are well-posed in all cases of mixed Diriehlet- Neuman problems. Waves can be generated in the tank by wavemakers, or be directly specified on the free surface. If required, absorbing layers can be specified on lateral boundaries. Node regridding to a finer resolution can be specified at any time step over selected areas of the free surface. Results are presented for both validation tests, with a permaneut wave propagation over constant depth, and for the computation of a 3D overturning wave over a ridge. Finally, one computation is presented for a case of 3D wave impact on a vertical wall.
Wave propagation up to overturning over slopes and complex bottom features, has been successfully modeled in twodimensional (2D) Numerical Wave Tanks (NWT), usually based on fully nonlinear potential flow equations (FNPF) expressed in a mixed Eulerian-Lagrangian formulation (MEL) (e.g., Grilli et al., 1996,1997; Grilli and Horrillo, 1999). Such calculations are in good agreement with laboratory experiments for intermediate water (e.g., Dommermuth et al., 1988), and for shallow slopes (e.g., Grilli et al., 1997). Ill the more recent 2D-NWTs, incident waves can be generated at one extremity, and reflected, absorbed, or radiated at the other extremity (e.g., Cldment, 1996; Grilli and Horrillo, 1997). In most cases, Laplace's equation is solved with a higher-order Boundary Element Method (BEM).
