08/09/2022 14:00 - LHSV, EDF'Lab Chatou, Salle D-003
It is our pleasure to welcome Alexandre Caboussat (HES-SO, associé EPFL) at our LHSV hydraulic laboratories, who will talk about "Simulation numérique du transport de sédiments basée sur un modèle de mélange "à une vitesse"
Numerical simulation of free surface flows with sediment dynamics
by Alexandre Caboussat -- Geneva School of Business Administration (HES-SO), Geneva, Switzerland and EPFL associate
Sediment transport is a crucial question in hydraulic and environmental engineering, for instance to model the sediment dynamics in rivers. We present a numerical model based on a mixture model for multiphase flows. The Navier-Stokes equations for incompressible flow are coupled with the dynamics of the particles’ concentration (transport, deposition and resuspension), and a volume-of-fluid approach for the tracking of the free surface between water and air.
The numerical algorithm relies on an operator-splitting method that decouples diffusion, advection and sedimentation processes.
A two-grid method is used for the space discretization. A well-chosen mix of finite elements, finite volumes and characteristics methods are dedicated to each sub-step of the time evolution algorithm.
The numerical model is validated through comparisons with 3D numerical experiments, focusing on sediment flushing, shear flow erosion, and dunes formation.