A fully three dimensional unstructured grid non-hydrostatic finite element coastal model

The non-hydrostatic model FINEL3D is based on the finite element method. In the model no approximations to the non-hydrostatic equations have been made. The model uses a 3-D fully unstructured grid and tetrahedral elements. The calculations presented here use the so called mini-element. In this paper the models capability to simulate internal flow and internal wave formation over small scale topography are considered. The flow of a stratified fluid over small scale topographic features in an estuary may generate considerable non-hydrostatic internal wave activity. The model is shown to accurately simulate internal trapped waves and internal lee waves. Differences between the analytical solutions and the model results are shown to be due to numerical diffusion.