Neha Yadala

Continuum modelling of dry granular flows over a circular cylinder in dense-flow regime

Granular flows are encountered everywhere in nature in the form of sand flowing down a pile, food grains poured into a container, rocks moving down the inclined plains, snow avalanches etc. They exhibit interesting features like formation of thin shear bands, dilation or compaction of the medium, and shear rate independence of stress in dense-flow regime. In addition, deformation is felt at a distance from the point of shear, suggesting the non-local behaviour of granular continua.

A recent continuum model proposed by Dsouza and Nott (2020), accounts for the non-local behaviour of grains and is known to capture dilatancy. So far, this model has been applied to a relatively simple flow, such as plane-shear flow, and the predictions were found to be in good agreement with discrete-particle simulations. However, the impact of non-local behaviour and density variations on the granular flow in complex situations such as flow over obstacles (encountered in terrestrial flows) and industrial equipment such as a hopper has not been explored.

The aim of this work is to study granular flow over a simplest cylindrical obstacle using the non-local model of Dsouza and Nott (2020). The continuum model is applied for a definite region around the cylinder to gain insights about the impact of velocity and density variations on the stress fields.