Dynamics of wetting revisited

Area of Science:

• Physical Chemistry
• Fluid Dynamics
• Materials Science

Background:

• Dynamic wetting describes liquid behavior on surfaces over time.
• Existing models attempt to explain spreading dynamics but have limitations.
• Accurate experimental data is crucial for validating these models.

Purpose of the Study:

• To analyze spreading-drop data across a wide time range.
• To evaluate the applicability of different dynamic wetting models.
• To assess the reliability of model selection based on experimental data.

Main Methods:

• Collected precise contact angle and droplet radius data for four liquids on silica surfaces.
• Utilized novel G-Dyna software for data analysis and model fitting.
• Applied hydrodynamic, molecular-kinetic, and combined theoretical models.

Main Results:

• G-Dyna software accurately processed hundreds of measurements.
• Analysis showed difficulty in definitively selecting the best-fit model.
• Parameter distributions and correlations provided insights into model performance.

Conclusions:

• Even high-quality data and robust fitting may not reliably distinguish between dynamic wetting models.
• Claims about model superiority require careful consideration of data set size and fitting stringency.
• The study highlights the complexities in validating theoretical models with experimental results.