Investigation of the mobile granular layer in bedload transport by laminar shearing flows

Pascale Aussillous (1) , Julien Chauchat (2) , Mickael Pailha (3) , Marc Médale (1) , Elisabeth Guazzelli (1)

1 IUSTI - Institut universitaire des systèmes thermiques industriels
2 LEGI - Laboratoire des Écoulements Géophysiques et Industriels [Grenoble]
3 LOCIE - LabOratoire proCédés énergIe bâtimEnt

The mobile layer of a granular bed composed of spherical particles is experimentally investigated in a laminar rectangular channel flow. Both particle and fluid velocity profiles are obtained using particle image velocimetry for different index-matched combinations of particles and fluid and for a wide range of fluid flow rates above incipient motion. A full three-dimensional investigation of the flow field inside the mobile layer is also provided. These experimental observations are compared to the predictions of a two-phase continuum model having a frictional rheology to describe particle-particle interactions. Different rheological constitutive laws having increasing degrees of sophistication are tested and discussed.

Domaines: Mécanique des fluides [physics.class-ph]; Mécanique des fluides [physics.class-ph]

Pascale Aussillous, Julien Chauchat, Mickael Pailha, Marc Médale, Elisabeth Guazzelli. Investigation of the mobile granular layer in bedload transport by laminar shearing flows. Journal of Fluid Mechanics, 2013, 736, pp 594-615. ⟨10.1017/jfm.2013.546⟩. ⟨hal-00915257⟩