Vers une méthodologie opérationnelle pour la caractérisation et la modélisation numérique de la dynamique des sédiments fins dans les retenues

Multi-dimensional numerical modelling (2D or 3D) enables to simulate the dynamics and evolution of sediment deposits in reservoirs, and can replace or complement physical modelling, which is intrinsically very limited for the case of cohesive sediment. Case studies are presented, which validate different steps necessary for the numerical modelling of sediments dynamics in reservoirs. Computation of bed shear stress by a 3D numerical model is validated by comparison with measurements on a physical model. Experience feedback on sediment characterization is presented. It concerns fall velocity and erodibility, in order to parameterize the model. Finally, an example of modelling of reservoir deposition including both cohesive and non-cohesive sediment is presented.