Last year, we performed a series of experiments to investigate the flow of an assembly of non-cohesive spherical grains in high gravity conditions. We studied the flow of beads out of a silo that was loaded in one of the gondolas of the Large Diameter Centrifuge (LDC) facility (located at ESTEC) in which an apparent gravity up to 20 times the Earth’s gravity can be established.
We studied in details a 2D silo in high gravity because this configuration allows to determine the local properties of the flow at the level of the aperture. As a function of the apparent gravity, we measured the velocity profiles and the packing fraction profiles for the various aperture sizes. We demonstrated the existence of a slip length for the flow at the level of the aperture, and we confirmed the validity of the Beverloo law for the discharge of silos.
S.Dorbolo et al., Granular Matter 15, 263 (2013) – PDF