title: Superstable granular heap in a thin channel.
abstract: We observed experimentally a new regime for granular flows in an inclined channel with a flow-rate-controlled system. For high flow rates, the flow occurs atop a static granular heap whose angle is considerably higher than those usually exhibited by granular heaps. The properties of such superstable heaps (SSH) are drastically affected by a change in the channel width W. This indicates that the unusual stability of these heaps can be accounted for by the flowing layer and its friction on the sidewalls. A simple depth-averaged model, assuming Coulomb friction, shows that the SSH angle scales as h/W (W being the channel width), and that grain size plays no part.
authors.affiliation: GMCM, Université Rennes 1, Batiment 11A, 35042 Rennes, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Taberlet
authors.forename: Patrick
authors.initials: P
authors.lastname: Richard
authors.forename: Alexandre
authors.initials: A
authors.lastname: Valance
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Losert
authors.forename: José Miguel
authors.initials: JM
authors.lastname: Pasini
authors.forename: James T
authors.initials: JT
authors.lastname: Jenkins
authors.forename: Renaud
authors.initials: R
authors.lastname: Delannay