Particle climbing along a vibrating tube: a vibrating tube that acts as a pump for lifting granular materials from a silo
Abstract
Granular material under the action of gravity flows down an incline tube or plane. This paper presents a phenomenon in which a granular material climbs along a vertically vibrating tube that is partially inserted in a granular silo. In this scenario the final climbing height increases with increasing vibration strength and tube insertion depth. However, the climbing velocity of the granular material does not monotonically increase with the climbing height. A transition height, at which the granular material has the highest climbing velocity, also exists. When the tube vibrates, the force between the tube and the particles varies periodically, thus inducing the directional climbing of particles. By analyzing the forces on the particles, we present a model that is qualitatively consistent with the experimental results.