Non-monotonic dependence of avalanche durations on particle velocities in the discharge of a silo

The distributions of avalanche times between successive clog events are analyzed in a silo discharged with conveyor belt. In previous work [Phys. Rev. Lett. 121 , 138001 (2018)], we measured the distribution sizes (in number particles) for same experiment, finding monotonous influence both outlet size and velocity particles clogging probability. Nonetheless, if durations instead sizes, minimum is observed when representing mean time as function particles. This phenomenon explained using kinematic arguments, which validated by experimental data. At time, this aims at highlighting importance discerning measuring avalanches terms or doing it