Numerical simulations of dense suspensions rheology using a dem-fluid coupled model

Abstract

The understanding of dense suspensions rheology is of great practical interest for both industrial and geophysical applications and has led to a large amount of publications over the past decades. This problem is especially difficult as it is a two-phase media in which particle-particle interactions as well as fluid-particle interactions are significant. In this contribution, the plane shear flow of a dense fluid-grain mixture is studied using the DEM-PFV coupled model. We further improve the original model: including the deviatoric part of the stress tensor on the basis of the lubrication theory, and extending the solver to periodic boundary conditions. Simulations of a granular media saturated by an incompressible fluid and subjected to a plane shear at imposed vertical stress are presented. The shear stress is decomposed in different contributions which can be examined separately: contact forces, lubrication forces and drag forces associated to the poromechanical couplings.