Eur. Phys. J. E 4, 233-239
Vertically shaken column of spheres. Onset of fluidizationS. Renard1, T. Schwager1, T. Pöschel1 and C. Salueña2
1 Humboldt-Universität, Charité, Institut für Biochemie, Monbijoustraße 2, D-10117 Berlin, Germany (http://summa.physik.hu-berlin.de/~kies/)
2 Humboldt-Universität, Institut für Physik, Invalidenstraße 110, D-10115 Berlin, Germany
(Received 21 August 2000 and Received in final form 30 October 2000)
The onset of surface fluidization of granular material in a vertically vibrated container, , is studied experimentally. Recently, for a column of spheres it has been theoretically found (see T. Pöschel, T. Schwager, C. Salueña, Phys. Rev. E 62, 1361 (2000)) that the particles lose contact if a certain condition for the acceleration amplitude holds. This result is in disagreement with other findings where the criterion was found to be the criterion of fluidization. We show that for a column of spheres a critical acceleration is not a proper criterion for fluidization and compare the results with theory.
81.05.Rm - Porous materials; granular materials.
83.70.Fn - Granular solids.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2001