Author(s): M. Di Natale; R. Greco
Linked Author(s): Roberto Greco
Keywords: Storm water discharge; Drowned flow; 2DH model; Radiation stress
Abstract: A mathematical model of the hydraulic behaviour of the outlet of a channel ending up into the sea in presence of opposing waves is presented. Aim of the model is to evaluate the entity of the surge determined by the waves in the outfall branch of a drainage network. A 2DH hydrodynamic model of the flow field is considered. In the momentum equations the radiaton stress tensor divergence is introduced, in order to take into account the wave-current interaction phenomenon. The evaluation of the wave field characteristics is made in a very simplified way, in order to simulate inner zone conditions up to the limit of wave breaking. The numerical integration is performed by means of a first order semi-implicite finite differences scheme. An explicit lagrangian approach is used to evaluate the substantial derivatives. The application of the model to a real test case shows how the surge in the final section of the drainage system is strongly dependent on the wave field characteristics, thus affecting the tailwater in the channel.
Year: 2003