Elongated grains in a hopper

T. Börzsönyi, Ellák Somfai, Balázs Szabó, Sandra Wegner, Ahmed Ashour, Ralf Stannarius

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1 Citation (Scopus)


Flow and clogging of granular materials in a 3-dimensional hopper is investigated experimentally. We use X-ray tomography and optical methods to study this phenomenon for spherical and elongated particles. The X-ray tomograms provide information on the bulk of the hopper filling, and allow to determine the particle positions and orientations inside the silo, as well as spatial variations of the local packing density. We find that particles show a preferred orientation and thereby an enhanced order in the flowing zone of the silo. Similarly to simple shear flows, the average orientation of the particles is not parallel to the streamlines but encloses a certain angle with them. The clogged state is characterized by a dome, i. e. the geometry of the layer of grains blocking the outflow. The number of grains forming this blocking layer is larger for elongated grains compared to the case of spheres of the same volume.

Original languageEnglish
Article number06017
JournalEPJ Web of Conferences
Publication statusPublished - Jun 30 2017
Event8th International Conference on Micromechanics on Granular Media, Powders and Grains 2017 - Montpellier, France
Duration: Jul 3 2017Jul 7 2017


ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Börzsönyi, T., Somfai, E., Szabó, B., Wegner, S., Ashour, A., & Stannarius, R. (2017). Elongated grains in a hopper. EPJ Web of Conferences, 140, [06017]. https://doi.org/10.1051/epjconf/201714006017