Spreading of a granular droplet.
The influence of controlled vibrations on the granular rheology is investigated in a specifically designed experiment in which a granular film spreads under the action of horizontal vibrations. A nonlinear diffusion equation is derived theoretically that describes the evolution of the deposit shape. A self-similar parabolic shape (the granular droplet) and a spreading dynamics are predicted that both agree quantitatively with the experimental results. The theoretical analysis is used to extract effective friction coefficients between the base and the granular layer under sustained and controlled vibrations. A shear thickening regime characteristic of dense granular flows is evidenced at low vibration energy, both for glass beads and natural sand. Conversely, shear thinning is observed at high agitation.
- Research Organization:
- Argonne National Lab. (ANL), Argonne, IL (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC); OUS; FOR
- DOE Contract Number:
- DE-AC02-06CH11357
- OSTI ID:
- 962536
- Report Number(s):
- ANL/MSD/JA-57026; PLEEE8; TRN: US200916%%17
- Journal Information:
- Phys. Rev. E, Vol. 76, Issue 2007; ISSN 1063-651X
- Country of Publication:
- United States
- Language:
- ENGLISH
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