Clogging in bidisperse granular flow: A parametric study

We have investigated the clogging behavior of aspherical particles flowing in a silo in the presence of a small amount of spherical particles. The primary focus of the work is to study the effects of particle shape and size of secondary spheres, using Discrete Element Method (DEM) simulations. We observe that the tendency of clogging increases for a small amount of secondary spheres but subsides at higher sphere content. This nonmonotonic dependence is reasoned out to be due to competing effects of local packing and reduced effective particle size at the exit observed while moving from low to high sphere volume fraction. The sensitivity of clogging to local packing of particles is also evident from the observed non-monotonic dependence on the size ratio and as well the dependence of clogging on aspect ratio of bulk particles. Overall, the clogging behavior is observed to be governed by the interplay between particle alignment and packing structure, which determines avalanche strength and arch formation.