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Updated: May 18, 2026
10:09
Fast Imaging Technique to Study Drop Impact Dynamics of Non-Newtonian Fluids
Published on: March 5, 2014
Initial spreading of low-viscosity drops on partially wetting surfaces
Koen G Winkels1, Joost H Weijs, Antonin Eddi
1Physics of Fluids Group, Faculty of Science and Technology, University of Twente, AE Enschede, The Netherlands.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 26, 2012
Summary
The initial spreading of low-viscosity liquid drops on surfaces is very fast. Our study reveals this rapid spreading is independent of surface wettability, with the contact radius growing with the square root of time.
Area of Science:
- Physics of liquids
- Surface science
- Materials science
Background:
- Liquid drop spreading on surfaces is a fundamental phenomenon.
- The initial dynamics involve a three-phase contact line but occur rapidly.
- Understanding initial spreading is crucial for various applications.
Purpose of the Study:
- To investigate the initial spreading dynamics of low-viscosity liquid drops.
- To explore previously unexamined length and time scales of drop spreading.
- To elucidate the mechanism of initial liquid-solid contact establishment.
Main Methods:
- Utilizing molecular dynamics simulations to model liquid-solid interactions at the nanoscale.
- Employing high-speed imaging to capture the fast initial spreading motion.
- Complementary experimental and computational approaches.
Main Results:
- Observed a spreading regime independent of substrate wettability.
- Determined the contact radius grows proportionally to the square root of time.
- Provided a detailed picture of initial liquid-solid contact formation.
Conclusions:
- The initial spreading of low-viscosity drops is governed by a universal mechanism.
- Wettability does not influence the early-stage spreading dynamics.
- The observed square-root-of-time dependency offers a new understanding of initial wetting.
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