Entropy Analysis in a Bubble Column Based On Ultrafast X-Ray Tomography Data


Entropy Analysis in a Bubble Column Based On Ultrafast X-Ray Tomography Data

Nedeltchev, S.; Schubert, M.

New ultrafast X-ray tomography data has been obtained in a bubble column (0.1 m in ID) operated with an air-deionized water system at ambient conditions. Raw reconstructed images were treated by both the information entropy (IE) and the reconstruction entropy (RE) algorithms in order to identify the main transition velocities in a bubble column. The IE values exhibited two well-pronounced minima at Ug=0.025 m/s and Ug=0.085 m/s identifying the boundaries of the homogeneous, transition and heterogeneous regimes. The reconstruction entropy extracted from the central region of the column’s cross-section exhibited only one characteristic peak at Ug=0.03 m/s, which was attributed to the transition from the homogeneous to the heterogeneous regime. This result implies that the transition regime is non-existent in the core of the column.

Keywords: Bubble column; Ultrafast X-ray tomography; Information entropy; Reconstruction entropy

  • Lecture (Conference)
    18th International Conference on Chemical, Biochemical and Biomolecular Engineering, 25.-26.02.2016, London, UK
  • Open Access Logo International Journal of Chemical, Molecular, Nuclear, Materials and Metallurgical Engineering 10(2016)2, 256-259

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Permalink: https://www.hzdr.de/publications/Publ-22858
Publ.-Id: 22858