Erosion dynamics of a granular bed in a quasi-bidimensional sluice-gate set-up

GONDRET, P.; RABAUDA, M.; MARTINO, R.; PATERSON, A.; PIVA, M.

Chatou

Simposio; Symposium on Two-phase Modelling for Sediment Dynamics in Geophysical Flows; 2013

Societe Hydrotechnique de France

The temporal evolution of a scour hole-dune system is investigated experimentally in a narrow rectangular quasi bidimensional channel without free surface interaction. The cell is partially filled at the bottom with a non-cohesive sediment and the scour is created locally by the erosive action of the strong water flow below a vertical sluice gate of varying gap. The interface dynamics of the granular bed is recorded by a video camera and analyzed. The erosion process is shown to be governed by a local Shields number that decreases with time until the erosion stops, leading to an asymptotic final hole/dune system.