Details

Autor(en) / Beteiligte

• Stannarius, Ralf
• Martinez, Diego Sancho
• Börzsönyi, Tamás
• Bieberle, Martina
• Barthel, Frank
• Hampel, Uwe

Titel

High-speed x-ray tomography of silo discharge

Ist Teil von

• New journal of physics, 2019-11, Vol.21 (11), p.113054

Ort / Verlag

Bristol: IOP Publishing

Erscheinungsjahr

2019

Link zum Volltext

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• The outflow of granular materials from storage containers with narrow outlets is studied by means of ultrafast x-ray computed tomography (UFXCT). The used acquisition speed of this tomograph is high enough to allow high-speed recording of two horizontal cross sections (each of them at a rate of 1000 images per second) of the container during the discharge of material. Analyzing space-time plots that were generated from the tomograms, we retrieve velocity profiles and packing structures in the container. We compare hard spherical grains with soft, low-friction hydrogel spheres. Their flow profiles are qualitatively different. While the hard spheres form stagnant zones at the container side walls, the hydrogel spheres with extremely low friction coefficient flow in all regions of the container. Moreover, a shell-like positional arrangement of the soft spheres induced by the container walls is revealed. The results obtained for the flow field structure confirm earlier conclusions drawn from sequences of x-ray tomograms of clogged states.