Dam-break dry granular flows: experimental and numerical analysis.

Granular flows have been the subject of several researches in the last years, not only in fluvial hydraulics and risk management but also in many other engineering applications, such as, for instance, material stockpiling and freights, food manufacturing and industrial processes. This research is aimed at giving a contribution in the comprehension of such phenomena, through the analysis of the results of a specific campaign of small-scale laboratory experiments of dry granular flows produced by dam breaks conducted in the Laboratory of Water Engineering (LIA) at University of Cassino and Southern Lazio, Italy, and of their numerical simulations. Tests have been performed with two different sands and different initial material heights in the reservoir. They provided data available for the validation of numerical models describing granular flows. Moreover, they may be used also for testing morphodynamic models adopted for the simulation of fluvial hydraulic processes in order to verify their capability of reproducing the behavior of the only solid phase. A depth-integrated two-phase model, originally developed for sediment transport in unsteady flows, is herein adopted to simulate the presented experiments. To this aim only the equations related to the solid phase are considered. The presented numerical results show a reasonable agreement with the final configurations of the dry granular dam breaks experimentally observed.