Phase-field model for quantitative analysis of droplet wetting

Area of Science:

• Computational physics and materials science.
• Surface science and fluid dynamics.

Background:

• Modeling liquid droplets on solid surfaces is crucial for understanding phenomena like wetting.
• Accurate prediction of excess surface energies and droplet profiles requires robust computational methods.
• Existing models may face challenges with volume conservation and interface width limitations.

Purpose of the Study:

• To develop a general phase-field formalism for analyzing three-dimensional, asymmetric liquid droplets on solid surfaces.
• To ensure strict volume conservation and accurately capture geometric profiles.
• To propose a method for interpreting data at vanishing interface widths.

Main Methods:

• A general phase-field formalism was developed.
• A nonlinear definition was employed for internal volume to ensure strict conservation.
• An extrapolation method was proposed to interpret data at finite interface widths, facilitating modeling as interface widths approach zero.
• A numerically tractable algorithm was implemented.

Main Results:

• The algorithm accurately predicts excess surface energies and geometric profiles of liquid droplets.
• It provides accurate predictions for wetting configurations on both external and internal cylinder surfaces.
• Quantitative agreement was demonstrated with established results from other models and computational techniques.

Conclusions:

• The presented phase-field formalism offers a robust and accurate method for studying liquid droplet behavior on solid surfaces.
• The developed algorithm successfully addresses challenges in volume conservation and interface width interpretation.
• This approach validates well against existing models, highlighting its utility in surface science and fluid dynamics research.