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Updated: Sep 24, 2025
08:02
Fabricating High-viscosity Droplets using Microfluidic Capillary Device with Phase-inversion Co-flow Structure
Published on: April 17, 2018
10.6K
Marangoni spreading and contracting three-component droplets on completely wetting surfaces
Dieter A Baumgartner1,2, Samira Shiri1,3, Shayandev Sinha1
1Rowland Institute, Harvard University, Cambridge, MA 02142.
Summary
This study reveals a novel boomerang-like wetting motion in ternary liquid mixtures, where droplets spread and then retract. This unique behavior enables efficient surface cleaning with minimal liquid volume.
Area of Science:
- Fluid dynamics
- Surface science
- Materials science
Background:
- Capillary forces govern droplet behavior in simple liquids.
- Evaporation in liquid mixtures introduces complex spatio-temporal modulation of forces.
- Marangoni flow direction critically influences droplet spreading or inhibition.
Purpose of the Study:
- To experimentally and numerically demonstrate antagonistic Marangoni flows in ternary mixtures.
- To investigate the resulting unique droplet wetting dynamics.
- To explore applications in surface processing, such as cleaning.
Main Methods:
- Experimental observation of sessile droplet dynamics.
- Numerical simulations of fluid behavior.
- Analysis of Marangoni flow interactions in ternary mixtures.
Main Results:
- Demonstrated the coexistence of two opposing Marangoni flows.
- Observed a 'boomerang-like' wetting motion: initial spreading followed by retraction.
- Showcased spread-retract-remove surface processing capability with minimal liquid volume.
Conclusions:
- Ternary mixtures exhibit complex wetting dynamics not seen in simple liquids.
- Antagonistic Marangoni flows can be harnessed for controlled droplet motion.
- This phenomenon offers a new paradigm for efficient, low-volume surface treatment.
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