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Updated: Jul 20, 2025
10:09
Fast Imaging Technique to Study Drop Impact Dynamics of Non-Newtonian Fluids
Published on: March 5, 2014
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Kinetic drop friction
Xiaomei Li1, Francisco Bodziony2, Mariana Yin2
1Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany.
Nature Communications
|July 29, 2023
Summary
Predicting liquid drop sliding velocity on tilted surfaces is challenging. This study introduces a friction coefficient to quantify dynamic wetting, improving understanding for various liquids and surfaces.
Area of Science:
- Physics
- Fluid Dynamics
- Materials Science
Background:
- Liquid drops sliding on tilted surfaces are common in nature and industry.
- Predicting drop sliding velocity and behavior remains a significant challenge.
- Understanding dynamic wetting is crucial for applications involving fluid-surface interactions.
Purpose of the Study:
- To quantitatively understand the factors governing liquid drop sliding on inclined surfaces.
- To develop a predictive model for drop sliding velocity and friction.
- To investigate the relationship between material properties, liquid viscosity, and dynamic wetting.
Main Methods:
- Experimental measurement of sliding velocity, contact dimensions, and contact angles for various liquids and surfaces.
- Empirical analysis of friction force as a function of liquid viscosity and sliding velocity.
- Definition and calculation of a dimensionless friction coefficient.
Main Results:
- The friction force acting on sliding drops can be empirically described by a power-law relationship with velocity.
- A dimensionless friction coefficient, specific to liquid-surface combinations, was determined.
- This coefficient ranges from 20 to 200 for the tested liquids and surfaces.
- Dynamic wetting requires this friction coefficient in addition to static contact angles.
Conclusions:
- A novel friction coefficient is introduced to characterize dynamic wetting of sliding liquid drops.
- This coefficient provides a material-specific parameter essential for predicting sliding behavior.
- The findings advance the quantitative understanding of fluid dynamics on inclined surfaces.
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