DEM analysis of the flow and friction of spherical particles in steel silos with corrugated walls

Steel silos with corrugated walls are widely used because they allow an increase of the wall buckling resistance, but corrugations affect the material flow and the forces applied over the walls. Silo design codes propose a method to estimate the friction on corrugated walls, but important aspects of the problem are not considered. This paper presents DEM simulations for a flat-bottom silo with different corrugation depths. Results show the differences in the friction of particles stored in a silo against a corrugated wall from a smooth wall, thus producing changes in many aspects such as flow, velocity of particles or friction coefficient. Flow rates and velocity of particles were higher for models with larger corrugation depths, especially for the initial period of discharge. Greater mobilization of particle-to-particle friction coefficient and higher values for contact normal forces were also detected as the value of the depth of the corrugation increased.