Collapse of a hemicatenoid bounded by a solid wall: instability and dynamics driven by surface Plateau border friction.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 35730763.
- Also identified by DOI 10.1039/d2sm00516f.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
The collapse of a catenoidal soap film when the rings supporting it are moved beyond a critical separation is a classic problem in interface motion in which there is a balance between surface tension and the inertia of the surrounding air, with film viscosity playing only a minor role. Recently [Goldstein <i>et al.</i>, <i>Phys. Rev. E</i>, 2021, <b>104</b>, 035105], we introduced a variant of this problem in which the catenoid is bisected by a glass plate located in a plane of symmetry perpendicular to the rings, producing two identical hemicatenoids, each with a surface Plateau border (SPB) on the glass plate. Beyond the critical ring separation, the hemicatenoids collapse in a manner qualitatively similar to the bulk problem, but their motion is governed by the frictional forces arising from viscous dissipation in the SPBs. We present numerical studies of a model that includes classical laws in which the frictional force <i>f</i><sub><i>v</i></sub> for SPB motion on wet surfaces is of the form <i>f</i><sub><i>v</i></sub> ∼ Ca<sup><i>n</i></sup>, where Ca is the capillary number. Our experimental data on the temporal evolution of this process confirms the expected value <i>n</i> = 2/3 for mobile surfactants and stress-free interfaces. This study can help explain the fragmentation of bubbles inside very confined geometries such as porous materials or microfluidic devices.