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 1, PAGES [159 - 168]
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