Abstract
Hypothesis: ‘Bridge splitting’ is considered in the case of capillary adhesion: a fixed total volume of liquid is split into multiple capillary bridges. Previous studies have shown that bridge splitting only enhances the capillary-induced adhesion force between two planar surfaces in specific circumstances. We hypothesise that bridge splitting significantly enhances the total adhesion force between rough surfaces, since mobile wetting bridges can naturally migrate to narrower gaps. This migration of capillary bridges should also provide a resistance to shear.
Numerical experiments: We theoretically consider an idealized system of many liquid bridges confined between two solid surfaces. By numerically calculating the shape of a single bridge, the total adhesion force is found as the number of bridges and roughness are varied. The resistance to shear is also calculated in the limit of strong surface tension or small shears.
Findings: Bridge splitting on a rough surface significantly enhances the adhesion force, with an enhancement that increases with the amplitude of the roughness; maximising over the number of bridges can increase the total adhesion force by an order of magnitude. Resistance to shear is shown to increase linearly with the translation velocity, and the behaviour of many such shearing bridges is quantified.
Numerical experiments: We theoretically consider an idealized system of many liquid bridges confined between two solid surfaces. By numerically calculating the shape of a single bridge, the total adhesion force is found as the number of bridges and roughness are varied. The resistance to shear is also calculated in the limit of strong surface tension or small shears.
Findings: Bridge splitting on a rough surface significantly enhances the adhesion force, with an enhancement that increases with the amplitude of the roughness; maximising over the number of bridges can increase the total adhesion force by an order of magnitude. Resistance to shear is shown to increase linearly with the translation velocity, and the behaviour of many such shearing bridges is quantified.
| Original language | English |
|---|---|
| Pages (from-to) | 514-529 |
| Number of pages | 16 |
| Journal | Journal of Colloid and Interface Science |
| Volume | 607 |
| Issue number | Part 1 |
| Early online date | 28 Aug 2021 |
| DOIs | |
| Publication status | Published - Feb 2022 |
Bibliographical note
Funding Information:The research leading to these results received funding from EPSRC Grant No. EP/N509711/1 (MB), the Corpus Christi Shand Green-MI Scholarship (MB), the European Research Council under the European Union’s Horizon 2020 Program/ERC Grant 637334 (DV) and a Philip Leverhulme Prize (DV). The data used to produce the plots within this paper and other findings of this study are available at: https://doi.org/10.5287/bodleian:9obJReeYo.
Funding Information:
The research leading to these results received funding from EPSRC Grant No. EP/N509711/1 (MB), the Corpus Christi Shand Green-MI Scholarship (MB), the European Research Council under the European Union's Horizon 2020 Program/ERC Grant 637334 (DV) and a Philip Leverhulme Prize (DV). The data used to produce the plots within this paper and other findings of this study are available at: https://doi.org/10.5287/bodleian:9obJReeYo.
Publisher Copyright:
© 2021 Elsevier Inc.
Keywords
- Capillary adhesion
- Roughness
- Shear resistance
- Surface tension
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Biomaterials
- Surfaces, Coatings and Films
- Colloid and Surface Chemistry