title: Unsteady granular flows down an inclined plane.
abstract: The continuum description of granular flows is still a challenge despite their importance in many geophysical and industrial applications. We extend previous works, which have explored steady flow properties, by focusing on unsteady flows accelerating or decelerating down an inclined plane in the simple shear configuration. We solve the flow kinematics analytically, including predictions of evolving velocity and stress profiles and the duration of the transient stage. The solution shows why and how granular materials reach steady flow on slopes steeper than the angle of repose and how they decelerate on shallower slopes. The model might facilitate development of natural hazard assessment and may be modified in the future to explore unsteady granular flows in different configurations.
authors.affiliation: Institute of Earth Sciences, Hebrew University, Givat Ram, 91904 Jerusalem, Israel.
authors.forename: Stanislav
authors.initials: S
authors.lastname: Parez
authors.affiliation: Institute of Earth Sciences, Hebrew University, Givat Ram, 91904 Jerusalem, Israel.
authors.forename: Einat
authors.initials: E
authors.lastname: Aharonov
authors.affiliation: Institut de Physique du Globe de Strasbourg, École et Observatoire des Sciences de la Terre, Universite de Strasbourg, CNRS, 5 Rue Descartes, 67084 Strasbourg Cedex, France.
authors.forename: Renaud
authors.initials: R
authors.lastname: Toussaint