title: Theoretical description of repeated surface-tension auto-oscillations.
abstract: A mathematical model is proposed to follow the behavior of a system where a droplet of a surfactant with limited solubility on the tip of a capillary under the free liquid surface dissolves in a container with a unity aspect ratio. Numerical simulations show that instability repeatedly arises and fades in the system, resulting in auto-oscillations of the surface tension in agreement with the experimental data. The system evolution during the oscillation is discussed in detail. It is established that the presence of a boundary in the radial direction is a necessary precondition for the appearance of the second and following oscillations.
authors.affiliation: Institute for Problems of Material Science, 03142 Kiev, Ukraine.
authors.forename: N M
authors.initials: NM
authors.lastname: Kovalchuk
authors.forename: D
authors.initials: D
authors.lastname: Vollhardt