Proceedings

EPJ E Colloquium - The role of acoustic streaming in vertically vibrated granular beds

Photo by Robert Hartley and co-workers at Duke University (Robert Behringer’s Group)

A recent EPJ E Colloquium by Jose Manuel Valverde looks at the fundamental physics that causes convection and fluidization in vibrated beds of particles with large inertia. The author examines the question of whether acoustic streaming arising from oscillatory viscous flows might play a role on the onset of convection and fluidization in vertically vibrated granular beds.

Acoustic streaming, first observed by Faraday in 1831, is an enigmatic phenomenon that has puzzled physicists for a long time. It occurs when a viscous fluid oscillates in the presence of a solid boundary. The dissipation of energy by viscous friction leads to a secondary steady circulation of fluid in a boundary layer near the surface of the solid, which enhances the gas-solid viscous interaction. Granular beds display, at sufficiently high vibrational intensities, surface patterns that bear a stunning resemblance to the surface ripples (Faraday waves) observed for low viscosity liquids. This suggests that the granular bed transits to a liquid-like regime, despite the large inertia of the particles.

The estimations in this Colloquium show that, thanks to acoustic streaming, the fluidization of beds of relatively large particles could be enhanced by oscillatory flows at not too large Reynolds numbers, giving rise to the observed liquid-like behavior. A similar mechanism could also be relevant to understanding geological events, such as fluidization of landslides and soil liquefaction by earthquakes and sound waves.

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