title: Steadily oscillating axial bands of binary granules in a nearly filled coaxial cylinder.
abstract: Granular materials often segregate under mechanical agitation such as flowing, shaking, or rotating, in contrast to an expectation of mixing. It is well known that bidisperse mixtures of granular materials in a partially filled rotating cylinder exhibit monotonic coarsening dynamics of segregation. Here we report the steady oscillation of segregated axial bands under the stationary rotation of a nearly filled coaxial cylinder for O(10(3)) revolutions. The axial bands demonstrate steady back-and-forth motion along the axis of rotation. Experimental findings indicated that these axial band dynamics are driven by global convection throughout the system. The essential features of the spatiotemporal dynamics are reproduced with a simple phenomenological equation that incorporates the effect of global convection.
authors: Department of Physics, Chiba University, Chiba 263-8522, Japan.
authors: Shio
authors: S
authors: Inagaki
authors: Department of Physics, Chiba University, Chiba 263-8522, Japan.
authors: Hiroyuki
authors: H
authors: Ebata
authors: Faculty of Life and Medical Sciences, Doshisha University, Kyoto 610-0394, Japan.
authors: Kenichi
authors: K
authors: Yoshikawa