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Effect of Viscosity on Bouncing Dynamics of Elliptical Footprint Drops on Non-Wettable Ridged Surfaces
1Department of Mechanical Engineering, Korea National University of Transportation, Chungju 27469, Korea.
Polymers
|December 28, 2021
Summary
The initial shape of a liquid drop significantly impacts its bouncing behavior and how long it stays on superhydrophobic surfaces. This study reveals how viscosity influences these asymmetric dynamics for elliptical drops.
Area of Science:
- Fluid dynamics
- Surface science
- Materials science
Background:
- Drop shape influences bouncing dynamics and residence time on superhydrophobic surfaces.
- Elliptical drops exhibit asymmetric dynamics due to shape-driven flow.
- The role of viscosity in these asymmetric dynamics remains under-investigated.
Purpose of the Study:
- Investigate the effect of viscosity on the asymmetric bouncing dynamics of elliptical drops.
- Analyze the impact of liquid properties, drop size, and velocity on bouncing and residence time.
- Understand the mechanisms governing residence time variations.
Main Methods:
- Numerical simulation using the volume-of-fluid method.
- Studied elliptical footprint drops with varying density, surface tension, and viscosity.
- Analyzed drop shape evolution during impact, spreading, retraction, and bouncing.
Main Results:
- Initial drop shape significantly alters bouncing dynamics and residence time.
- Viscosity plays a crucial role in the asymmetric dynamics of elliptical drops.
- Shape evolution analysis provides insight into residence time variations.
Conclusions:
- Understanding viscous drop impact on textured surfaces is vital for industrial applications.
- Findings aid in designing spraying devices and macro-textured surfaces for specific impact conditions.
- Provides insights for developing surfaces like icephobic coatings.
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