Modeling of waves overtopping and flooding in the coastal reach by a non-hydrostatic model

Abstract

This paper describes a model package that simulates wave transformation, overtopping and flooding in coastal reaches. The present model is extended from the non-linear shallow water equations by means of including the non-hydrostatic pressure terms in the momentum equations. The transformed vertical coordinate, i.e. the σcoordinate, is adopted to fit the free surface and the uneven bottom. When a wave is ready to break, the non-hydrostatic model is locally switched to hydrostatic model by suppressing the dispersive effects. The breaking wave front is handled as a shock, and the shock wave can be simulated by non-linear shallow water equations with conservative numerical strategy. The treatments of the wave breaking and the shoreline motion are validated by experiments. One extensive application of the model to predict flooding induced by large waves or storm surge is presented to verify the efficiency of the present model in modeling of wave transformation and flooding over complex geometry in coastal reaches.