Author(s): J. -M. Hervouet; E. Razafindrakoto; C. Villaret
Linked Author(s):
Keywords: Navier-Stokes equations; Finite elements; Finite volumes; Free surface hydrodynamics; Tidal flats
Abstract: the hydroinformatic system Telemac is based on unstructured grids, it includes a Shallow Water Equations solver (Telemac-2D), a Navier-Stokes solver in 3 dimensions with a free surface (Telemac-3D), and a morphodynamics model for suspension and bed load (Sisyphe). Dealing with dry zones is now common practice but hinders a lot classical advection schemes. We present here a new class of advection schemes combining the best properties of implicit finite element and explicit finite volume schemes. The resulting capabilities of the method are: mass-conservation (water and tracers), be it in 2D or 3D, monotonicity (depth and tracers), along with very large time steps, as there is no CFL condition, even with tidal flats, which was the main goal. The technique works in parallel and can also be used to gain flexibility in building highly distorted 3D meshes between bottom and free surface. It can also be used to solve the Exner equation for bed load transport. Test cases are presented.
Year: 2011