Abstract
An oscillating bubble attached to a tip of a capillary is used for probing interfacial properties of liquids containing surface-active agents. Nevertheless, available theories even for the case of pure liquid are not satisfactory. In this contribution, we therefore present results of a linear inviscid theory for shape oscillations of a spherical bubble, which is in contact with a solid support. The theory allows determining eigenmodes (i.e. eigenfrequencies, eigenmode shapes and damping of eigenmode oscillations), but also response of the bubble shape to a motion of its support or to volume variations. Present theory covers also the cases previously analyzed by Strani and Sabetta (J. Fluid Mech., 1984) and Bostwick and Steen (Phys. Fluids, 2009), and it can be applied to both bubbles and drops. The theory has been compared to experiments. Good agreement is found for the case of small bubbles, which have spherical static shape. Experimental results for larger bubbles and drops deviate from the theory, if a neck is formed. It is shown that this deviation correlates well with a ratio of bubble volume to the maximum volume, when a detachment occurs.
Highlights
We present results of a linear inviscid theory for shape oscillations of a spherical bubble, which is in contact with a solid support
Shape oscillations of drops and bubbles are extremely sensitive to the presence of surface active agents at the liquid-gas interface
Volume variations are imposed to the drop in order to vary periodically its interfacial area [2]
Summary
Shape oscillations of drops and bubbles are extremely sensitive to the presence of surface active agents at the liquid-gas interface For this reason, bubble/drop oscillations are of interest, if the interfacial properties like the interfacial elasticity or viscosity are studied [1], especially in the range of high frequencies. For analyzing the shape oscillations, an assumption of irrotational flow remains reasonable, if the liquid is pure The eigenmodes of such a supported bubble or drop are predicted by irrotational analyses of Strani and Sabetta [4] and of Bostwick and Steen [5]. The case studied by Bostwick and Steen was reexamined more recently with the use of more suitable approaches [6, 7] None of these analyses covers the cases with variable volume or moveable support, encountered in the equipment
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
