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Updated: Jun 20, 2026
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High Throughput Analysis of Liquid Droplet Impacts
Published on: March 6, 2020
Effects of surface roughness on droplet impact dynamics
Joe Ghossein1, Chinmay Kendurkar1, Jonathan B Boreyko2
1Kevin T. Crofton Department of Aerospace and Ocean Engineering, Virginia Tech, Blacksburg, VA, USA. joe20ghossein@vt.edu.
Soft Matter
|June 18, 2026
Summary
This study introduces a new energy model to predict droplet spreading on rough surfaces, improving accuracy by accounting for surface roughness and wettability. The findings enhance models for water droplet impact dynamics on various textured substrates.
Area of Science:
- Fluid Dynamics
- Surface Science
- Materials Science
Background:
- Existing droplet impact models fail to account for surface roughness.
- Superhydrophobic textures and smooth surfaces have been the focus of past research.
- Predicting maximum spreading ratio (βmax) is crucial for understanding droplet dynamics.
Purpose of the Study:
- Investigate the influence of surface roughness and wettability on water droplet impact dynamics.
- Focus on the maximal spreading diameter of Wenzel droplets at low splashing regimes.
- Develop a new energy model incorporating surface roughness effects.
Main Methods:
- Varied surface mean roughness amplitude (Ra) on glass, PETG, and aluminum substrates via laser etching.
- Controlled surface wettability from hydrophilic to hydrophobic.
- Developed a modified energy model for elastic (We < 30) and inelastic (We ≥ 30) impact regimes.
Main Results:
- Surface roughness significantly influences droplet spreading, deviating from universal models for roughness ratios (r) ≳ 2.
- The new roughness-dependent energy model shows excellent agreement across all tested roughness ratios.
- The model successfully incorporates surface energy and viscous dissipation modifications due to roughness.
Conclusions:
- Surface roughness is a critical factor in droplet spreading dynamics.
- The developed model extends predictive capabilities for water droplet spreading on rough substrates.
- This work provides a more comprehensive framework for understanding droplet-surface interactions.
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