Controlling the breakup of toroidal liquid films on solid surfaces

Edwards, Andrew M. J., Ruiz Gutiérrez, Élfego, Newton, Michael I., McHale, Glen, Wells, Gary, Ledesma Aguilar, Rodrigo and Brown, Carl V. (2021) Controlling the breakup of toroidal liquid films on solid surfaces. Scientific Reports, 11 (1). p. 8120. ISSN 2045-2322

Preview

Text s41598-021-87549-5.pdf - Published Version Available under License Creative Commons Attribution 4.0. Download (5MB) | Preview

Abstract

The breakup of a slender filament of liquid driven by surface tension is a classical fluid dynamics stability problem that is important in many situations where fine droplets are required. When the filament is resting on a flat solid surface which imposes wetting conditions the subtle interplay with the fluid dynamics makes the instability pathways and mode selection difficult to predict. Here, we show how controlling the static and dynamic wetting of a surface can lead to repeatable switching between a toroidal film of an electrically insulating liquid and patterns of droplets of well-defined dimensions confined to a ring geometry. Mode selection between instability pathways to these different final states is achieved by dielectrophoresis forces selectively polarising the dipoles at the solid-liquid interface and so changing both the mobility of the contact line and the partial wetting of the topologically distinct liquid domains. Our results provide insights into the wetting and stability of shaped liquid filaments in simple and complex geometries relevant to applications ranging from printing to digital microfluidic devices.

Actions (login required)

View Item

Downloads