Dam Break Flow Modelling and Geographical Distribution of the Roughness Coefficient

Dam break flow modelling is a major field of research. In order to enable risk
analysis in the downstream valleys of dams, 2D numerical simulations are of prime
interest. These are based on the conservative set of shallow water equations. Beyond
their numerical implementation, the challenge of the computation relies on the ability
to handle very huge sets of high-precision data, in order to get the highest possible
accuracy, whereas the computational time must remain realistic for simulations
carried out on real valleys topography.
In this paper, a simulation on about 2 500 000 cells is presented. Particularly, the
results are compared and discussed regarding especially the exploitation of landuse
data for the roughness. Beyond the examples of validation, the relevance of the
developed methodology appears to be essential in the framework of risk analysis.