MODELLING THE FLOW AROUND AN ISLAND AND A HEADLAND: APPLICATION OF A TWO MIXING LENGTH MODEL WITH TELEMAC3D

Numerical modelling of the circulation around islands and headlands is a challenging task with bottom friction and eddy viscosity controlling the formation of wakes and eddies. The eddy viscosity terms in such configurations can become predominant and an implicit solver is desirable to maintain reasonable computational time. An approach based on coupling the horizontal mixing length to the vertical one following Stansby (2003) is implemented into TELEMAC3D (Hervouet, 2007). This development is then tested against two different datasets of laboratory experiments, the one representing the flow around an island and another one the oscillatory tidal flow in the vicinity of a headland. Comparisons with conventional eddy viscosity models are presented.