ABSTRACT
The present paper deals with the avalanche regime of granular material in a rotating drum partially filled with glass beads. We examine the influence of the size distribution of the particles on the angles of avalanche and repose. The comparison of the values of angles for single size particles and for particles with a size distribution shows that both angles are lower for single size particles. In a second part, we study the influence of the walls on the critical angles of stability and repose of the material. Both angles are increased as long as the walls are spaced by less than 20 diameters of particles. Above this value, the angles are no more affected. Finally, we study geometrically similar systems: the size of the drum in number of particles is kept constant.
