Granular discharge and clogging for tilted hoppers

摘要: We measure the flux of spherical glass beads through a hole as systematic function both tilt angle and diameter, for two different size beads. The discharge increases with diameter in accord Beverloo relation horizontal vertical holes, but latter case larger small-hole cutoff. For large holes decreases linearly cosine angle, vanishing smoothly somewhat below repose. small it vanishes abruptly at smaller angle. conditions zero are discussed context clogging phase diagram flow state vs ratio to grain size.