THERMAL SCIENCE

International Scientific Journal

THE INFLUENCE OF ACOUSTIC FIELD AND FREQUENCY ON HYDRODYNAMICS OF GROUP B PARTICLES

ABSTRACT
Sound Assisted Fluidized Bed (SAFB) of group B particles (180μm glass bead) has been studied in a 46mm I.D. column with aspect ratios of 1.4 and 2.9. A loudspeaker mounted on the top of the bed was supplied by a function generator with square wave to generate the sound as the source of vibration of the fluidized bed. The sound pressure level (referred to 20μpa) was varied from 102 to 140dB and frequencies from 70Hz to 170Hz were applied. The effects of sound pressure level, sound frequency and particle loading on the properties of SAFB were investigated. The experimental result showed that the minimum fluidization velocity decreased with the increase in sound pressure level, also minimum fluidization velocity was varied with variation of frequencies. At resonance frequency minimum fluidization velocity was found to be minimum. The bed height did not show an appreciable increase in presence of high acoustic field and at resonant frequency. Minimum fluidization velocity verses frequency curve in presence of sound intensity varied with variation of bed weight.
KEYWORDS
PAPER SUBMITTED: 2010-01-20
PAPER REVISED: 2010-04-12
PAPER ACCEPTED: 2010-08-20
DOI REFERENCE: https://doi.org/10.2298/TSCI100120054L
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2011, VOLUME 15, ISSUE Issue 1, PAGES [159 - 168]
REFERENCES
  1. Chirone R. & Massimila L., "Sound Assisted Aeration of Beds at Cohesive Solids", Chemical Engg. Science, 49, 1184-1194, 1994.
  2. Chirone R., Massilila L. and Russo S., " Bubbling fluidization of a cohesive powder in an acoustic field", fluidization VII, proceedings of 7th Engg. Conference on fluidization Engg. Foundation, 545-553, 1992.
  3. Chirone R., Massimila L., and Russo S., "Bubble-free fluidization of a cohesive powder in an Acoustic field", Chemical Engg.Science, 48, 41-52, 1993.
  4. Chirone R., Russo P., Massimila L., and Russo S., "The influence of the frequency of Acoustic waves on sound assisted fluidization of beds of fine particles", Powder Technology, 82,53-57,1995.
  5. Geldart D., "Types of Gas Fluidization", Powder Technology, 7, 285-292, 1973.
  6. Guo Qingjie, Liu Huie, Shen Wenzhong, Yan Xianghong and Jia Rugao, "Influence of sound wave characteristics on fluidization behaviors of ultrafine particles", Chemical Engineering Journal, 119, 1-9,2006.
  7. Leu L.P. and Chen C.M., " Hydrodynamic study of fluidization of group B particles in an Acoustic field", proc. Asian Conf. Fluidization Bed and Three phase Reactors, Fukoka, Japan, 13-18, 1994.
  8. Leu L.P. and Huang C.T., "Fluidization of cohesive powders in a sound wave Vibrated fluidized bed", AIChE symp. ser., 90, 301, 1994.
  9. Leu L.P., Li J.T. and Chen C.M., "Fluidization of group B particles in an acoustic field", Powder Technology, 94, 23-28, 1997.
  10. Levy E.K. and Celest Brian, "Combined effects of Mechanical and Acoustic Vibrations on Fluidization of Cohesive Powder", Powder Technology. 163, 41-50, 2006.
  11. Levy E.K., Herrera C.A. and Masaki T., "Bubbling fluidization of fine powders in a high Intensity acoustic field", proc. International Fluidization conference, Durango, Colorado, 1998.

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence