Proceedings

EPJE Colloquium: Dense granular flows - fluidity revisited

Local shear rate ˙Γ for a system of frictional soft grains
Bouzid et al.

In this new EPJ E Colloquium, a group of authors from ESPCI, Univ. Paris-Diderot and Univ. P.M. Curie use the interpretive frame-work of non-locality to describe the rheology and fluidity in dense granular flows. Is a “good fitting” of the velocity profiles sufficient to demonstrate the validity of a particular model for non-locality?

The article reviews and compares various approaches based on different constitutive relations and choices for the fluidity parameter, focusing on the kinetic elasto-plastic model introduced by Bocquet et al. [Phys. Rev. Lett 103, 036001 (2009)] for soft matter and adapted for granular matter by Kamrin et al. [Phys. Rev. Lett. 108, 178301 (2012)], as well as the gradient expansion of the local rheology μ(I) that the authors presented in Phys. Rev. Lett. 111, 238301 (2013).

The authors point out that, in order to discriminate between these approaches, one must go beyond the predictions derived from linearisation around a uniform stress profile, such as those obtained in a simple shear cell. Finally the authors discuss future tests, to better understand the mechanisms at the origin of non-local effects, that should be based on the nature of the chosen fluidity parameter and the related boundary conditions, as well as the hypothesis made to derive the models and the mechanisms underlying their dynamics.

This was our first experience of publishing with EPJ Web of Conferences. We contacted the publisher in the middle of September, just one month prior to the Conference, but everything went through smoothly. We have had published MNPS Proceedings with different publishers in the past, and would like to tell that the EPJ Web of Conferences team was probably the best, very quick, helpful and interactive. Typically, we were getting responses from EPJ Web of Conferences team within less than an hour and have had help at every production stage.
We are very thankful to Solange Guenot, Web of Conferences Publishing Editor, and Isabelle Houlbert, Web of Conferences Production Editor, for their support. These ladies are top-level professionals, who made a great contribution to the success of this issue. We are fully satisfied with the publication of the Conference Proceedings and are looking forward to further cooperation. The publication was very fast, easy and of high quality. My colleagues and I strongly recommend EPJ Web of Conferences to anyone, who is interested in quick high-quality publication of conference proceedings.

On behalf of the Organizing and Program Committees and Editorial Team of MNPS-2019, Dr. Alexey B. Nadykto, Moscow State Technological University “STANKIN”, Moscow, Russia. EPJ Web of Conferences vol. 224 (2019)

ISSN: 2100-014X (Electronic Edition)

© EDP Sciences