Related Experiment Video
Updated: Aug 16, 2026
07:18
Measuring the Interaction Force Between a Droplet and a Super-hydrophobic Substrate by the Optical Lever Method
Published on: June 14, 2019
Off-Centered Droplet Impact on a Single-Triangular-Ridge Superhydrophobic Surface
Meixuan Li1,2, Jie Wu1,2, Tongwei Zhang2,3
1State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Yudao Street 29, Nanjing, Jiangsu210016, China.
Langmuir : the ACS Journal of Surfaces and Colloids
|August 14, 2026
Summary
Off-centered droplet impact on superhydrophobic surfaces reduces contact time by inducing asymmetric retraction. This study categorizes droplet behaviors and provides models to predict outcomes for applications like self-cleaning.
Area of Science:
- Fluid dynamics
- Surface science
- Materials science
Background:
- Asymmetric retraction of droplets on surfaces can reduce contact time.
- Superhydrophobic surfaces are engineered to minimize liquid adhesion.
- Understanding droplet dynamics is crucial for various technological applications.
Purpose of the Study:
- To investigate droplet morphological evolution and contact time on a single-triangular-ridge superhydrophobic surface after off-centered impact.
- To categorize droplet behaviors based on off-centered distance and develop a predictive classification model.
- To explore the influence of Weber number and off-centered distance on contact time and identify mechanisms for its reduction.
Main Methods:
- Numerical simulations of droplet impact and evolution.
- Classification of droplet behaviors into five types based on off-centered distance.
- Analysis of spreading, contraction, and splitting processes.
- Quantification of droplet shape and characteristic time to elucidate contact time reduction mechanisms.
Main Results:
- Droplet behaviors were categorized into five types based on off-centered distance.
- A theoretical classification model was proposed to predict these types.
- Off-centered impact and ridge compression significantly altered droplet velocity distribution.
- Contact time was found to be primarily determined by retraction time, influenced by ridge compression at small off-centered distances.
Conclusions:
- Off-centered impact on triangular-ridge superhydrophobic surfaces leads to asymmetric retraction and reduced contact time.
- The study provides a theoretical framework for predicting droplet behavior and contact time.
- Findings offer insights into asymmetric bouncing and guidance for self-cleaning and anti-icing strategies.
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