A Sequential Approach for the Simulation of Granular Flow whithin Full Scale Silos Using the Distinct Element Method

PARISI DANIEL R.; MASON SAMUEL; LABORDE MIGUEL A.; MARTINEZ JUAN

San Diego, California, USA.

Conferencia; 2001 Mechanics And Materials Conference; 2001

The proposed method consists in partitioning the silo into n horizontal sub-domains or layers that are analyzed sequentially, and in determining pressures and velocities at the virtual boundaries between the adjacent layers. The method works first downwards for determining the pressures, then upwards for determining the velocities. The sequence begins by the top layer whose upper boundary is subject to a known pressure (equal to zero in case of a free surface) and whose pressure at the lower boundary is unknown. A displacement is imposed to this lower boundary until the limit wall traction and a steady value of the searched pressure are reached. The computed pressure is then applied on the top boundary of the lower layer. This sequential stress reconstruction is repeated downwards until the upper boundary of the bottom layer of the silo. At this step, the simulation of the emptying of this last layer is started and the velocity of its upper boundary can be obtained. This velocity is used as the bottom boundary condition for the base of the upper layer. By continuing this upward velocity reconstruction until the top layer of the silo, the velocity field is obtained within the whole silo.