Abstract:  We report the experimental findings on horizontal transport and density wave in granular materials in a vertically vibrated annular container with a sawtooth?shaped base. The inner and outer diameters of the container are
183 mm and 190 mm, respectively. T he container is excited by Br?el & Kj? r 4805, which is controlled by a vibration exciter control Br?el & Kj? r 1050. The driving frequency f and the dimensionless acceleration amplitude
?= 4? 2 f 2 A/ g ( A is the driving amplitude and g the gravitational acceleration) are used as two control parameters. The particles are copper spheres with a diameter of 3 mm. A high speed camera ( Redlake MASD MotionScope PCI
2000sc) is used to record the movements of all spheres. An image processing technique is used to track the locations of all particles. We use the vibrating container as the reference frame in image processing. Every chosen region of
the pictures is divided into three stripes uniformly in vertical direction. T he experimental results are obtained by anassembly average. As ? increases to and beyond a critical value ? c = 1 ? 8, the granular layer fluidizes from top to
lower parts. The velocity distribution of grains indicates that the horizontal granular flow appears, and the fitting curves of densities indicate that the density wave appears in the layer. We have observed that from bottom to top the
granular flow velocity decreases and the direction reverses, while the density wave propagates against the granular flow. As driving frequency is increased, the granular flow velocity decreases monotonically, while the amplitude of
density wave has a maximum at 18Hz. The mechanism for the granular flow is the ratchet effect of the sawtooth of bottom of the container, while the exploration on the mechanism for the density wave is underway.