Rheological response of granular materials under dynamic conditions

Channel Flows of Granular Materials and Their Rheological Implications

Stability of Granular Materials under Vertical Vibrations

The influence of periodic vibrations on the granular flow of materials is of great interests to scientists and engineers due to both theoretical and practical reasons. In this paper, the stability of a vertically vibrated granular layer is examined by linear stability analysis. This includes two major steps, firstly, the base state at various values of mass holdup (Mt) and energy input (Qt) is ...

How granular materials deform in quasistatic conditions

Based on numerical simulations of quasistatic deformation of model granular materials, two rheological regimes are distinguished, according to whether macroscopic strains merely reflect microscopic material strains within the grains in their contact regions (type I strains), or result from instabilities and contact network rearrangements at the microscopic level (type II strains). We discuss th...

Incremental response of granular materials: DEM results

We systematically investigate the incremental response of various equilibrium states of dense 2D model granular materials, along the biaxial compression path (σ11 < σ22, σ12 = 0). Stress increments are applied in arbitrary directions in 3dimensional stress space (σ11,σ22,σ12). In states with stable contact networks we compute the stiffness matrix and the elastic moduli, and separate elastic and...

Efficient Voronoi volume estimation for DEM simulations of granular materials under confined conditions

When the discrete element method (DEM) is used to simulate confined compression of granular materials, the need arises to estimate the void space surrounding each particle with Voronoi polyhedra. This entails recurring Voronoi tessellation with small changes in the geometry, resulting in a considerable computational overhead. To overcome this limitation, we propose a method with the following f...