Premium
The Bjerknes effect: Explaining pulsed‐flow behavior in bubble columns
Author(s) -
Waghmare Y. G.,
Knopf F. Carl,
Rice Richard G.
Publication year - 2007
Publication title -
aiche journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.958
H-Index - 167
eISSN - 1547-5905
pISSN - 0001-1541
DOI - 10.1002/aic.11200
Subject(s) - breakage , bubble , mechanics , amplitude , sauter mean diameter , breakup , oscillation (cell signaling) , penetration (warfare) , weber number , range (aeronautics) , mass transfer , chemistry , thermodynamics , physics , materials science , mathematics , optics , turbulence , reynolds number , composite material , biochemistry , operations research , nozzle
New experimental data for a range of gas velocities from 0.1 to 1.5 cm/s are explained by an elementary theory that combines the effect of bubble retardation owing to Bjerknes forces with the breakage relationship of Hinze in a pulsed‐bubble column. A frequency range from 10 to 30 Hz, and two amplitudes of fluid oscillation were used in the 8.9 cm column: 1.66 and 2.46 mm. Experimental values of volumetric mass‐transfer coefficient for oxygen dissolution followed predictions of theory using a modified penetration model. A new phenomenon was observed and was predictable from theory, namely “flooding”, which arises when bubbles are partially or fully retarded by Bjerknes forces at the point of injection. Under flooding conditions, transport enhancement levels off as frequency or amplitude is increased. Bubble‐size distribution was measured as a function of frequency, and the calculated Sauter‐mean diameter was satisfactorily fitted by the Hinze breakage formula. © 2007 American Institute of Chemical Engineers AIChE J, 2007