MechSys is a programming library for the implementation of simulation tools in mechanics. Its source code is mainly written in C++ with easier to use templates for further customization.

Potential applications include, for instance, solid mechanics and the dynamics of granular materials using the discrete element method, and both computational fluid dynamics and computational electromagnetics using the lattice Boltzmann method.

Discrete Element Method (DEM)

The Discrete Element Method is a powerful simulation scheme for soil, solid and fracture mechanics. Its fundamentals are simple, the body of study is divided in elements (could represent the individual grains in soils or pieces of solid in rocks) and Newton's laws are solve numerically to obtain their behaviour in time. Its popularity has grown in time since it reproduce naturally the elasto-plastic behaviour of soils and rocks and has many applications both in academy and industry. Mechsys DEM solver has the capability to deal with particles of general shape.

Lattice Boltzmann Method (LBM)

The Lattice Boltzmann Method was created to numerically solved the Boltzmann equation coming from statistical mechanics. It was shown that under some conditions it can also solve the Navier Stokes equations. Furthermore, it has proven to be a general Partial Differential Equation (PDE) solver. Mechsys has the traditional Navier Stokes solver module (LBM), a solver for Maxwell equations of electromagnetism (EMLBM) and the set of advection diffusion equations (ADLBM). As a novelty, Mechsys also couples DEM with LBM to have a powerful tool to simulate problems involving fluid and solid interaction.


Mechsys development has been sponsored by the University of Queensland, the Australian Research Council (ARC Discovery Grant DP140100490 Qualitative and quantitative modelling of hydraulic fracturing of brittle materials) and the Advance Queensland Fellowship program (Grant AQ-15188 Pushing the boundaries of current numerical geotechnical modelling capabilities )


Some animations produced by MechSys' simulations are shown below. Additional animations can be found in Sergio Torres' Youtube channel for simulations created from Mechsys.

LBM Simulations

An imbibition-drainage simulation within a porous medium

A cavitation simulation where a fluid forms a liquid bubble

DEM Simulations

A triaxial test with general shaped particles

A brazilian test to determine the tensile strength of rocks

DEM+LBM Simulations

A DEM dolphin spinning and diving into an LBM pool

A DEM duck with lower density of liquid LBM fluid floating on it

EMLBM Simulations

A cross section area of a dipole antenna, both the electric (parallel to the plane) and the magnetic (perpendicular to the plane) are shown

An electric pulse (the electric field vector is going out from the screen) propagates between two media of different dielectric permittivity changing its speed and wavelength

Featured publications

This is a selected list of scientific articles where Mechsys has been used.

Behraftar S, Galindo-Torres SA, Scheuermann A, Williams DJ, Marques EAG, Janjani H (2017) Validation of a novel discrete-based model for fracturing of brittle materials. Computers and Geotechnics, http://dx.doi.org/10.1016/j.compgeo.2016.08.029
Zhang P, Galindo-Torres SA, Tang H, Jin G, Scheuermann A, Li L (2016) Lattice Boltzmann simulations of settling behaviors of irregularly shaped particles Physical Review E. https://doi.org/10.1103/PhysRevE.93.062612
To H.D., Scheuermann A., Galindo-Torres SA (2016) Sequential sphere packing by trilateration equations. Granular Matter , http://dx.doi.org/10.1007/s10035-016-0666-5
Galindo-Torres SA, Scheuermann A, Li L (2015) Boundary effects on the Soil Water Characteristic Curves obtained from lattice Boltzmann simulations. Computers and Geotechnics, http://dx.doi.org/10.1016/j.compgeo.2015.09.008
Gerolymatou E, Galindo-Torres SA, Triantafyllidis T (2015) Numerical Investigation of the Effect of Preexisting Discontinuities on Hydraulic Stimulation. Computers and Geotechnics, http://dx.doi.org/10.1016/j.compgeo.2015.05.013
HMD Harshani, Galindo-Torres SA, Scheuermann A (2015) Micro-mechanical analysis on the onset of erosion in granular materials. Philosophical Magazine, http://dx.doi.org/10.1080/14786435.2015.1049237
To H.D., Scheuermann A., Galindo-Torres SA (2014) Primary fabric fraction analysis of granular soils. Acta Geotechnica Special Issue: Hydraulic instabilities in granular materials Theory and Experiments , http://dx.doi.org/10.1007/s11440-014-0353-9
Galindo-Torres SA, Scheuermann A, Williams DJ, Muhlhaus HB (2013) A micro-mechanical approach for the study of contact erosion. Acta Geotechnica Special Issue: Hydraulic instabilities in granular materials Theory and Experiments , dx.doi.org/10.1007/s11440-013-0282-z
Galindo-Torres SA (2013) A coupled Discrete Element Lattice Boltzmann Method for the simulation of fluid-solid interaction with particles of general shapes Computer Methods in Applied Mechanics and Engineering , dx.doi.org/10.1016/j.cma.2013.06.004
Galindo-Torres SA, Pedroso DM, Williams DJ, Muhlhaus HB (2013) Strength of non-spherical particle assemblies under triaxial and shearing loading configurations. Granular Matter, dx.doi.org/10.1007/s10035-013-0428-6
Galindo-Torres SA, Scheuermann A, Li L, Pedroso DM, Williams DJ (2013) A lattice Boltzmann model for studying transient effects during imbibition-drainage cycles in unsaturated soils. Computer Physics Communications, 184(4), 1086-1093. dx.doi.org/10.1016/j.cpc.2012.11.015
Galindo-Torres SA, Scheuermann A, Li L (2012) A numerical study of the permeability in a tensorial form for laminar flow in anisotropic media. Physical Review E, 86, 046306. dx.doi.org/10.1103/PhysRevE.86.046306
Galindo-Torres SA, Pedroso DM, Williams DJ, Li L (2012) Breaking processes in three-dimensional bonded granular materials with general shapes. Computer Physics Communications, 183(2), 266-277. dx.doi.org/10.1016/j.cpc.2011.10.001
Galindo-Torres SA, Pedroso DM (2010) Molecular dynamics simulations of complex shaped particles using Voronoi-based spheropolyhedra. Physical Review E, 81, 061303. dx.doi.org/10.1103/PhysRevE.81.061303
Galindo-Torres SA, Marroquin F, Wang Y, Pedroso DM, Castano J (2009) Molecular dynamics simulation of complex particles in three dimensions and the study of friction due to nonconvexity. Physical Review E, 79, 060301. dx.doi.org/10.1103/PhysRevE.79.060301

Copyright of the papers rests with a variety of different parties. They are made available solely on the same basis that the researcher would supply a single copy of a paper to an individual. It is up to you to ensure that your use of a paper does not infringe copyright law.