%0 Journal Article
	%A Stoyan Nedeltchev and  Markus Schubert
	%D 2016
	%J International Journal of Chemical and Molecular Engineering
	%B World Academy of Science, Engineering and Technology
	%I Open Science Index 110, 2016
	%T Entropy Analysis in a Bubble Column Based on Ultrafast X-Ray Tomography Data
	%U https://publications.waset.org/pdf/10004308
	%V 110
	%X By means of the ultrafast X-ray tomography facility, data were obtained at different superficial gas velocities UG 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 RE 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 flow regime. This result implies that the transition regime is non-existent in the core of the column.

	%P 271 - 274