Granular flows on a dissipative base

Michel Yves Louge (1) , Alexandre Valance (2) , Paul Lancelot (3) , Renaud Delannay (2) , Olivier Artières (4)

1 MAE - Sibley School of Mechanical and Aerospace Engineering
2 IPR - Institut de Physique de Rennes
3 TU Delft - Delft University of Technology
4 TenCate Geosynthetics - TenCate Geosynthetics France [Bezons]

We study inclined channel flows of sand over a sensor-enabled composite geotextile fabric base that dissipates granular fluctuation energy. We record strain of the fabric along the flow direction with imbedded fiber-optic Bragg gratings, flow velocity on the surface by correlating grain position in successive images, flow thickness with the streamwise shift of an oblique laser light sheet, velocity depth profile through a transparent side wall using a high-speed camera, and overall discharge rate. These independent measurements at inclinations between 33 • and 37 • above the angle of repose at 32.1 ± 0.8 • are consistent with a mass flow rate scaling as the 3/2 power of the flow depth, which is markedly different than flows on a rigid bumpy boundary. However, this power changes to 5/2 when flows are forced on the sand bed below its angle of repose. Strain measurements imply that the mean solid volume fraction in the flowing layer above the angle of repose is 0.268 ± 0.033, independent of discharge rate or inclination.

Mots clés: Granular Flow; boundary conditions

Domaines: Autre [cond-mat.other]; Mécanique des fluides [physics.class-ph]

Michel Yves Louge, Alexandre Valance, Paul Lancelot, Renaud Delannay, Olivier Artières. Granular flows on a dissipative base. Physical Review E : Statistical, Nonlinear, and Soft Matter Physics, 2015, 92 (2), pp.022204. ⟨10.1103/PhysRevE.92.022204⟩. ⟨hal-01185913⟩