Two-dimensional dam-break simulation over movable beds with an unstructured mesh

This paper reports the application of a two-dimensional (2D) depth-averaged model to dam break flows over alluvial sand beds with an initial bed step. The model applies the Finite Element Method to discretize the computational domain using an unstructured mesh made of triangular elements. Two downstream boundary conditions were tested: zero (dry) and non-zero (wet) initial water depths. The model successfully reproduced the two types of transient waves observed in the experiments: the hydraulic jump produced with wet downstream condition and the surge moving over an initially dry bed. Since the present sediment transport model applied a single layer for sediment transport, comparison and discussion with results of a previous one-dimensional (1D) two-layer model are also provided.