  We investigated the clogging behavior observed during the flow of aspherical
particles from a silo in the presence of spherical particles of different sizes
and proportions using flow visualization experiments and discrete element
method (DEM) simulations. The size of the avalanche, essentially the tendency
of clogging, exhibits non-monotonic dependence on the spherical particle volume
fraction. For small enough content of spherical particles, the clogging
tendency intensifies, whereas it reduces rapidly for high enough spherical
particle fractions, with a minimum in between. The non-monotonic behavior is
observed to persist over for different spherical particle sizes. The overall
behavior is shown to arise due to competing effects between the localized total
particle fraction influencing avalanche strength and mean size of the particles
exiting the silo, influencing the probability of arch formation.
