# Fluid-solid coupling

From Yade

## Contents

# DEM-PFV (Pore scale Finite Volumes) coupling

A new method for efficiently coupling the DEM with fluid flow is being developed as part of Yade. The development started as part of Emanuele Catalano's PhD (Chareyre et al. 2011), and later included other developments.

The first video is the simulation of an injection of fluid below a granular bed. The problem is 3D, a cutting plane goes is used near the injection point. Color denotes fluid pressure.

The video on the right shows the flow of particle subjected to gravity and horizontal fluid flow. The periodic boundary conditions for the fluid are implemented by Donia Marzougui (PhD 3SR, Grenoble).

# 2D Solid-fluid coupling by associating DEM with LBM (lattice Boltzmann method)

The lattice Boltzmann method to describe the fluid dynamics has been coupled with the discrete element method in Yade. The implementation, currently limited to 2D cases, was initiated by Luc Scholtès and further developed by Franck Lominé (Lominé et al. 2013) during their postdoc in GeM Institute (Nantes, France).

The first video show the free fall of two particles in a fluid initially at rest (i.e. the fluid motion is induced by the particle displacements). The second video show an application of the coupled method to study the hole erosion in granular assemblies (a pressure drop is applied to the fluid from the left to the right, and particles are detached and transported under the action of the fluid flow).

# Model of a wet sand with rising water table

With the capillary law in Yade it is possible to model a wet sand with capillary forces. During the calculation the liquid bridges break from the bottom to the top (water table visualized by a blue face). This simulates a rising water table. The calculation was performed with multi-threading option on six cores. Hence there is a indeterminism, that entails to non-reproducibility of each calculation. Approximatly 10 percent of the calculations show no settlement (see right side in the video).

# SPH - 2D Dambreak simulation

Simulation of a 2D Dambreak Benchmark Test with the meshless Weekly Compressible Smoothed Particle Hydrodynamics (WCSPH) method. The high viscous fluid is driven by gravity force (done by Sebastian Borrmann, IMFD, TU Freiberg).