Kinematics of the discharge of flat particles from model silos

The present work aims at two main objectives: validation of former equations developed for predicting the discharge flow of particles from silos but, in this case, for flat (oblate) lentil grains, and characterization of the kinematics of those grains at the outlet of the silo for both mass and funnel flow regimes. Special emphasis is placed in describing the way in which the flat grains arrange in their way out of the silo opening. This is presented through a spatiotemporal analysis of the particles at the outlet of the hopper. Results demonstrated that, although the collective behavior of the flow can be represented by those theoretical approaches, the vertical velocity distributions during mass flow regime are incorrectly described by a continuum perspective and have to be revised. On the other hand, the parabolic vault hypothesis seems to be still adequate for describing the velocity profile in the funnel flow regime. Graphical abstract