2D flood modelling: the case of Tous dam break

Vasilis Bellos, George Tsakiris

Friday 3 july 2015

14:30 - 14:45h at Oceania Foyer (level 0)

Themes: (T) Flood risk management and adaptation, (ST) Flooding along in rivers and coasts

Parallel session: 16L. Flood risk - Flooding

In this study, the in-house FLOW-R2D model is used to simulate the flood event of Tous dam break which occurred in Sumacárcel, Spain, in 1982. This fully hydrodynamic model is based on the Shallow Water Equations in two-dimensions (2D-SWE) solved by a modified McCormack numerical scheme (Finite Difference Method) incorporating artificial viscosity. In a previous research, FLOW-R2D model was extensively tested using several scenaria and data from analytical and experimental studies. In the present study, the results of the model are compared with real data of the flood of Tous dam break, collected in the framework of the IMPACT Project. During the process of simulation, attention may be given to the factors creation uncertainties such as the boundary conditions (upstream and downstream) and the type of friction modelling. For the upstream boundary conditions, the inflow flood-hydrograph (proposed by the IMPACT project), is simulated by the FLOW-R2D model. An attempt is made to incorporate procedures in the model for describing the hysteresis phenomenon of the discharge-water elevation rating curve. Regarding the downstream conditions the open boundary condition is endorsed. As a final step of this study, a sensitivity analysis for some major parameters is performed to identify the dominant factors creating uncertainty in the water depth and velocity results produced by the model.