| Issue |
EPJ Web Conf.
Volume 140, 2017
Powders and Grains 2017 – 8th International Conference on Micromechanics on Granular Media
|
|
|---|---|---|
| Article Number | 03090 | |
| Number of page(s) | 4 | |
| Section | Granular flow | |
| DOI | https://doi.org/10.1051/epjconf/201714003090 | |
| Published online | 30 June 2017 | |
https://doi.org/10.1051/epjconf/201714003090
Wall roughness and nonlinear velocity profiles in granular shear flows
1 LMGC, UMR 5508 CNRS – Université de Montpellier, 163 rue Auguste Broussonnet, 34090 Montpellier, France
2 〈MSE〉 2, UMI 3466 CNRS-MIT, CEE, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge 02139, USA
3 LMT, ENS Paris-Saclay / CNRS / Univ. Paris-Saclay, 61 Av. du Président Wilson, 94235 Cachan Cedex, France
* e-mail: paul.schuhmacher@umontpellier.fr
Published online: 30 June 2017
Inhomogeneous velocity profiles in granular flows are well known from both experiments and simulations, and considered as a hallmark of nonlocal behavior. By means of extensive contact dynamics simulations, we show that the sigmoidal velocity profiles in 2D flows of rigid disks are controlled by the roughness of driving boundary walls. We find that the velocity profile becomes linear for a critical value of wall roughness up to an exponential decay close to the walls with a characteristic length that does not depend on the flow thickness and rate. We describe the velocity profiles by introducing a state parameter that carries wall perturbation. By assuming that the local shear rate is a linear function of the state parameter, we obtain an analytical expression that fits velocity profiles. In this model, the nonlinear velocity profiles are explained in terms of the effects of wall roughness as boundary condition for the state parameter.
© The Authors, published by EDP Sciences, 2017
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.