  The flow of elliptical particles out of a 2-dimensional silo when extracted
with a conveyor belt is analyzed experimentally. The conveyor belt - placed
directly below the silo outlet - reduces the flow rate, increases the size of
the stagnant zone, and it has a very strong influence on the relative velocity
fluctuations as they strongly increase everywhere in the silo with decreasing
belt speed. In other words, instead of slower but smooth flow, flow reduction
by belt leads to intermittent flow. Interestingly, we show that this
intermittency correlates with a strong reduction of the orientational order of
the particles at the orifice region. Moreover, we observe that the average
orientation of the grains passing through the outlet is modified when they are
extracted with the belt, a feature that becomes more evident for large
orifices.
