Numerical Simulation of Shoaling Broad-Crested Internal Solitary Waves

The interaction between fully nonlinear Miyata-Choi-Camassa (MCC) internal solitary waves and topographic slopes are modeled by direct numerical simulation. The immersed boundary method is employed to describe the no-slip boundary of the slopes and a novel iterative Neumann boundary condition (INBC) enforcement strategy is proposed to ensure local mass conservation. The wave Reynolds numbers Re-w used in the present work (similar to 10(4)), although less than those of field scales (10(6)-10(7)), but are an order of magnitude greater than those in most laboratory scale experiments and previous numerical simulations (similar to 10(3)). In the present study, three main internal wave breaking types (collapsing, plunging, and surging) together with two mixed mode breaking types (collapsing-plunging and plunging-surging) are observed for MCC wave shoaling process. The different breaking mechanisms are found to be related to the internal Iribarren number. New breaking regimes, breaking location criterion, and the maximum velocity prediction are also proposed. (C) 2017 American Society of Civil Engineers.