The first half of this talk will discuss several techniques for rapidly simulating granular flows. By carrying out a mesoscopic analysis of large-scale DEM simulations, a model of dense granular rheology can be refined and tested. This can then be used as the basis of a multiscale simulation technique that runs much faster than DEM and would be appropriate for problems in real-time control and optimization.

The packing fraction is an important quantity in analyzing dense granular flow, and small changes can often be associated with a very different mechanical response. Accurately calculating the local packing fraction is challenging, but can be done using the Voronoi tessellation, and the second half of this talk will discuss a free software library, Voro++, that has been developed as part of this work. While other mature software libraries exist, Voro++ makes use of a direct construction in which each Voronoi cell is computed individually. This perspective is often useful in many physical applications that make use of cell-based statistics. The library is designed to be easily incorporated into other programs, and provides a flexible framework for handling walls and complex boundary conditions.

Host: Mikhail Shashkov