Flow and clogging behavior of mixtures of low-friction soft and frictional rigid spheres in a quasi-two-dimensional silo*

Flow and clogging of a mixture of low-friction deformable beads with frictional hard beads of similar size were studied in a quasi-two-dimensional (2D) silo. Previous work has demonstrated that silo discharge is significantly different for low-friction deformable grains and conventional frictional hard particles. Here we show that the addition of a small amount of frictional hard beads to an ensemble of low-friction deformable beads already has significant consequences. We compare the outflow velocities and the duration of non-permanent clogs for different compositions of the mixtures. Experimental results are compared with numerical simulations.