Collaborators: Prof Itai Einav, Prof Sasha Puzrin, Dr Pierre Rognon
One of the most readily observed effects of grainsize variation in a granular material is its tendency to segregate during flow. Granular materials segregate for many reasons and under many conditions.
Small differences in size, density, or even surface roughness, can cause the particles to segregate while flowing. While generally granular materials can be described as a continuum, and hence as fluids, there is no analogous segregative term in fluid flow.
This project began with a simple numerical model of granular segregation, explaining the important physical processes relevant to the phenomenon. Once the physics was well understood, a rigorous continuum model was developed that described segregation in terms of changes in the local grainsize distribution of the material. Experimental evidence of this phenomenon was even found! More recently, segregation was coupled with comminution in another simple numerical model to explain the grainsize distribution evolution for natural avalanches, landslides and debris flows.
If you’re looking for some code to play around with, have a look here.