Three-Dimensional Cellular Automaton Model of Segregation of Granular Materials in a Rotating Cylinder

Binary mixtures of granular materials often exhibit segregation along the axis of a horizontal rotating cylinder. It is well known that segregation occurs radially at first, forming a buried core of one component. Later, alternate banding starts to form. This is axial segregation. There is no three-dimensional model that is capable of depicting transition from radial to axial segregation. We propose a cellular automaton model in which particles slide on the surface, and show that this model successfully reproduces these segregation processes.