Non-intrusive characterization of particle size changes in fluidized beds using recurrence plots

Research output: Contribution to journalArticlepeer-review


  • Chiya Savari
  • Rahmat Sotudeh-Gharebagh
  • Reza Zarghami
  • Navid Mostoufi

Colleges, School and Institutes

External organisations

  • Univ. of Tehran


An on-line method is developed for monitoring of mean particle size in fluidized beds using pressure fluctuations (PFs) and acoustic emissions (AE) signal by recurrence plot (RP) and recurrence quantification analysis (RQA). PFs and AE signals of a lab-scale fluidized bed were measured simultaneously at various superficial gas velocities and mean particle sizes. Although the AE signals are often very complicated due to many different acoustic sources in the bed, applying RP analyses showed that small changes in mean particle size can be detected by visual comparison of AE-RP structures, while this cannot be distinguished by graphical RP analysis of PFs. Moreover, the hydrodynamics of the bed was inspected through RQA analysis of both signals. For this purpose, recurrence rate, determinism, laminarity, average length of diagonal and vertical lines were extracted from RPs showing the effect of an increase in the mean particle size.


Original languageEnglish
Pages (from-to)3547-3561
Number of pages15
JournalAIChE Journal
Issue number10
Early online date5 Apr 2016
Publication statusPublished - 26 Apr 2016


  • acoustic emissions, fluidized bed, particle size, pressure fluctuations, recurrence plot