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Measuring the Interaction Force Between a Droplet and a Super-hydrophobic Substrate by the Optical Lever Method
Published on: June 14, 2019
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Symmetry-Breaking Drop Bouncing on Superhydrophobic Surfaces with Continuously Changing Curvatures.
1Department of Mechanical Engineering, Korea National University of Transportation, Chungju 27469, Korea.
Polymers
|September 10, 2021
Summary
Controlling drop bouncing on curved surfaces depends on drop shape and surface curvature. Ellipsoidal drops on curved surfaces amplify asymmetries, influencing bounce dynamics and residence time for applications like water repellency.
Area of Science:
- Fluid dynamics
- Surface science
- Materials engineering
Background:
- Controlling drop residence time is crucial for applications like self-cleaning and anti-icing surfaces.
- Drop bouncing dynamics are influenced by initial shape and surface interactions.
Purpose of the Study:
- Investigate bouncing features of spherical and ellipsoidal drops on curved surfaces.
- Analyze the impact of drop ellipticity and surface curvature on drop residence time.
Main Methods:
- Numerical simulations of drop impact dynamics.
- Experimental verification of simulation results.
- Systematic investigation of surface anisotropy and drop ellipticity effects.
Main Results:
- Ellipsoidal drop shapes amplify mass and momentum asymmetries during impact on curved surfaces.
- Drop bouncing characteristics are highly dependent on geometric relations between drops and surfaces.
- Residence time is strongly correlated with initial surface curvature and drop ellipticity.
Conclusions:
- Momentum asymmetry is the underlying principle for modifying drop residence time on curved surfaces.
- Understanding these dynamics offers practical implications for heat transfer and water repellency.
- The study provides insights into drop behavior on bio-inspired curved surfaces.
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