Numerical Simulation for a Granular Flow

Abstract

The numerical simulation for a multi-particle system of rigid polyhedrons is presented.
The computational method that is applied, Atomized efforts Contact Dynamics respecting the Clasius-Dunheim inequality, assumes that the particles have constant velocities on small time intervals and the
forces due to contacts or gravity are applied only in the limits of such intervals under the form of percussions.
Therefore the velocities of the particles have instantaneous time-discontinuities at discrete time.
A constrained minimization problem must be solved to get the new velocities of each particle after the time interval. The convergence of the Uzawa method applied to this problem is studied and the conjugate
gradient method is applied for solving the unconstrained minimization step.