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Breakup of liquid filaments
Alfonso A Castrejón-Pita1, J R Castrejón-Pita, I M Hutchings
1Department of Engineering, University of Cambridge, Cambridge, United Kingdom.
Physical Review Letters
|March 10, 2012
Summary
The breakup of liquid filaments into droplets depends on viscosity and dimensions. High viscosity or small aspect ratios prevent fragmentation, leading to filament shortening instead.
Area of Science:
- Fluid dynamics
- Surface phenomena
Background:
- Liquid filament behavior is governed by surface tension, viscosity, and initial dimensions.
- Surface tension drives competing processes of filament breakup (pinching-off) and shortening.
Purpose of the Study:
- To experimentally determine the conditions governing liquid filament breakup into droplets.
- To identify the key dimensionless parameters controlling filament stability.
Main Methods:
- Investigated liquid filaments across a range of aspect ratios and Ohnesorge numbers.
- Analyzed the interplay between capillary and viscous forces.
Main Results:
- Identified two dimensionless quantities: aspect ratio and Ohnesorge number, as critical predictors of filament fate.
- Demonstrated that high liquid viscosity or small aspect ratios inhibit droplet formation.
Conclusions:
- The outcome of liquid filament evolution (droplet formation vs. shortening) is predictable based on aspect ratio and Ohnesorge number.
- Filament stability is enhanced by increased viscosity or reduced initial aspect ratio.
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