  The stationary flow field in a quasi-two-dimensional hopper is investigated
experimentally. The behavior of materials consisting of beads and elongated
particles with different aspect ratio is compared. We show, that while the
vertical velocity in the flowing region can be fitted with a Gaussian function
for beads, in the case of elongated grains the flowing channel is narrower and
is bordered with sharper velocity gradient. For this case, we quantify
deviations from the Gaussian velocity profile. Relative velocity fluctuations
are considerably larger and slower for elongated grains.
