Europhys. Lett.
Volume 68, Number 4, November 2004
Page(s) 515 - 521
Section Electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics
Published online 13 October 2004
Europhys. Lett., 68 (4), pp. 515-521 (2004)
DOI: 10.1209/epl/i2004-10228-0

The growth of a Super Stable Heap: An experimental and numerical study

N. Taberlet, P. Richard, E. Henry and R. Delannay

Groupe Matériaux et Matière Condensée, Université Rennes 1 Bât. 11A, Campus Beaulieu, 35042 Rennes Cedex, France

received 27 July 2004; accepted in final form 15 September 2004
published online 13 October 2004

We report experimental and numerical results on the growth of a Super Stable Heap (SSH). Such a regime appears for flows in a thin channel and for high flow rate: the flow occurs atop a nearly static heap whose angle is stabilized by the flowing layer at its top and the side wall friction. The growth of the static heap is investigated in this paper. A theoretical analysis inspired by the BRCE formalism predicts the evolution of the growth process, which is confirmed by both experiments and numerical simulations. The model allows us to link the characteristic time of the growth to the exchange rate between the "moving" and "static" grains. We show that this rate is proportional to the height of the flowing layer even for thick flows. The study of upstream traveling waves sheds new light on the BCRE model.

45.70.Ht - Avalanches.
45.70.Mg - Granular flow: mixing, segregation and stratification.
83.10.Mj - Rheology: Molecular dynamics, Brownian dynamics.

© EDP Sciences 2004