A New Method for Flow Regime Identification in a Fluidized Bed based on Gamma-Ray Densitometry and Information Entropy


The Accurate Identification of the Boundaries of the Main Flow Regimes in Fluidized Beds is Very Important Since the Degrees of Mixing and Mass and Heat Transfer Depend on the Prevailing Flow Regime. Both the Minimum Fluidization Velocity UMf (0.103 M·s -1) and the Transition Velocity UTrans (0.12 M·s -1) to Bubbling Fluidization Regime Have Been Successfully Identified based on a Newly Developed Maximum Information Entropy (IEMax) Algorithm Applied to Gamma Photon Time Series. the Latter Are Recorded by Means of Gamma-Ray Densitometry Scans Performed in an Air-Polyethylene Fluidized Bed (0.438 M in ID) Operated at Ambient Conditions. a Comparison with the Kolmogorov Entropy (KE) Algorithm Has Found that the New Approach Yielded More Accurate Transition Velocities. the Value of UMf is Also Validated by Means of the Proles of Both Bed Pressure Drop and Bed Height, respectively. It Has Been Found, However, that These Parameters Are Not Capable of Identifying the Second Transition Velocity UTrans. It is Demonstrated that the UMf Value Identified on the Basis of IE Max is Theoretically Predictable. in the Bubbling Fluidization Regime, a Simple Correlation between Both the KE and IEMax Values is Developed. © 2012 the Society of Chemical Engineers, Japan.


Chemical and Biochemical Engineering

Keywords and Phrases

Flow regime identification; Gas-solids fluidized bed; Kolmogorov entropy; Maximum information entropy; Regime transition velocities

International Standard Serial Number (ISSN)


Document Type

Article - Journal

Document Version

Final Version

File Type





© 2023 The Authors, All rights reserved.

Publication Date

27 Mar 2012

This document is currently not available here.