We present below some of the most important softwares developed by the members of the group for the simulation of granular media. We distinguish between “generalist” softwares and problem-oriented programs. These include both solvers for time-stepping and pre- or post-processing codes for the sample preparation or data processing, as well as graphical display. A basic or minimalist software involves simple-shaped particles interacting via linear elastic repulsion and a Coulomb friction. More developed programs include enriched shapes and interactions. The most advanced programs deal with multiphysics problems involving an interstitial fluid or evolving composition such as particle fragmentation. In general, granular simulations are time-intensive and various degrees of code optimization (solver, contact detection, neighbor sorting...) are necessary for enhanced efficiency.
gdm-tk 2D/3D, tool-kit for granular dynamics methods
gdm-tk is a C++ toolkit (library) dedicated to granular dynamics methods. It does not necessary provide a turnkey solution for granular dynamics simulations, but it rather aims to provide a data structure with some tools that work with it and allows scientists to develop very eﬃciently within the context of granular dynamics methods. For example, there are functions to read/write ﬁles, or to perform calculations (e.g. stresses, force distributions, anisotropies).
DEMbox is a C++ code for discrete element methods (mainly based on explicit schemes) with a set of facilities to extent the models. For example, new shapes, force-laws, integration schemes, neighborhood constructor, limit conditions controls can easily be defined and add. DEMbox also comes with pre-processing commands (mainly to build samples), and processing tools that can be apply during or after the computation.
MGC2D - Solid Bonding DEM
MGC-2D is a 2D command line utility designed to compute the mechanical behavior of granular aggregates. This code, written in C, is based on theMolecular Dynamics (MD) method. It can take into account various interaction laws (contact, friction, adhesion), but its originality lies in its ability to account for solid bonding between particles. It can also handle thermodynamic parameters such as the damage of the bonds or swelling and shrinking of particles.
mgpost 2D/3D - DEM Visualisation
mgpost is a tool for post-processing and visualization of 2D or 3D DEM simulations. The source code can be freely be downloaded.
Tapio-k 2D/3D Molecular Dynamics
tapio-K is a code written in C for 2D or 3D DEM simulations. Newton’s second law is integrated by means of the velocity Verlet algorithm for spherical bodies. Boundary conditions focus on common geomechanical devices (Casagrande/Jenike shear cell, triaxial cell with membrane, 3-axis cell with 6 rigid walls, oedometer) but also on (e.g.) silo with trapdoor, mono-periodic conditions for tracked vehicle or granular ﬂows. In addition to common contact laws (linear/Hertz-Mindlin contact and Coulomb friction), the code includes various cohesion force-laws. In particular, the capillary cohesion due to the combined action of surface tension and suction operates in diﬀerent formulations. Since the spatial distribution of the capillary bonds mainly governs the strength, several (empirical) models are implemented.