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Title: Non-local continuum modelling of steady, dense granular heap flows
Dense granular heap flows are common in nature, such as during avalanches and landslides, as well as in industrial flows. In granular heap flows, rapid flow is localized near the free surface with the thickness of the rapidly flowing layer dependent on the overall flow rate. In the region deep beneath the surface, exponentially decaying creeping flow dominates with characteristic decay length depending only on the geometry and not the overall flow rate. Existing continuum models for dense granular flow based upon local constitutive equations are not able to simultaneously predict both of these experimentally observed features – failing to even predict the existence of creeping flow beneath the surface. In this work, we apply a scale-dependent continuum approach – the non-local granular fluidity model – to steady, dense granular flows on a heap between two smooth, frictional side walls. We show that the model captures the salient features of both the flow-rate-dependent, rapidly flowing surface layer and the flow-rate-independent, slowly creeping bulk under steady flow conditions.  more » « less
Award ID(s):
1552556
PAR ID:
10084103
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Journal of Fluid Mechanics
Volume:
831
ISSN:
0022-1120
Page Range / eLocation ID:
212 to 227
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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