Discrete element modelling and simulation

Nano to Micro/Macro (Micro-macro simulation methods)

This technique allows to study the dynamics of systems characterised by a large number of spherical particles, which can interact in different ways:

- elastic or elasto-plastic impacts, which are typical of dry granular systems;

- thermal and/or fluid dynamic forces (e.g., liquid bridges), which allow to include for instance the heat transfer between particles during impacts;

- electrostatic forces, or other potentials;

- cohesive forces, which allow to include the “stickiness” and the aggregation of particles.

Specific additional models can be developed and included in the simulations in order order to evaluate the effect of wear of materials due to particle impact, or the fluid dynamic transport of particles.

Example numerical simulations that can be performed fall in the case of so-called “mesoscale” systems, for instance:
- mixing and segregation of materials;

- mineral and pharmaceutical processing;

- powder metallurgy;

- friction and (liquid or solid) lubrication.

This technique is not perfectly suitable for nanoscale systems, for which molecular dynamics approaches have shown better performance, as well as for extremely large systems which would require an unreasonably large number of particles.