ISSN:
1089-7666
Source:
AIP Digital Archive
Topics:
Physics
Notes:
In previous numerical studies [Lee and Wang, J. Fluid Mech. 188, 411 (1988); Pelekasis et al., J. Fluid Mech. 230, 541 (1991)], it has been shown that when an inviscid and nonconcentric liquid shell undergoes a finite-amplitude capillary oscillation, its enclosed bubble undertakes a slow translational oscillation relative to the shell. In the present work, we study the effects of viscosity on the slow motion, in both free and forced capillary oscillations. It is found that in a free oscillation, the shell cannot become concentric because the oscillations are damped by viscosity before centering occurs. In a forced oscillation which is sustained by an external source such as a modulated acoustic radiation pressure, centering does occur when the slow oscillations are damped. The predicted centering of the shell takes place more slowly than that observed in experiments [Wang et al., J. Colloid Interface Sci. 165, 19 (1994)]. However, it is noted that a comparison with experiments is not appropriate at this time, since the shell in the experiments had an uncontrolled rotation in the acoustic potential well. © 1996 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.869045
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