Molecular Dynamics Study on Bubble Behaviors on a Grooved Surface with Different Roughnesses and Wetting Conditions
Mian Yu1, Bingheng Li1, Lianfeng Wu2
1College of Electromechanical Engineering, Qingdao University of Science and Technology, Qingdao 266061, China.
Langmuir : the ACS Journal of Surfaces and Colloids
|October 24, 2025
Summary
Molecular dynamics simulations reveal that increasing surface roughness and hydrophilicity significantly accelerate bubble generation. Enhanced surface properties improve nucleate boiling performance for engineering applications.
Area of Science:
- Nanoscale science and engineering
- Fluid dynamics and heat transfer
- Materials science
Background:
- Nucleate boiling is crucial for efficient heat transfer in many engineering applications.
- Understanding bubble dynamics at the nanoscale is key to optimizing boiling performance.
- Surface properties like roughness and wettability significantly influence heat transfer efficiency.
Purpose of the Study:
- To investigate nanoscale bubble nucleation, growth, coalescence, and departure dynamics.
- To determine the effects of surface roughness and wettability on bubble dynamics.
- To provide insights for optimizing nucleate boiling in engineering systems.
Main Methods:
- Conducting molecular dynamics (MD) simulations.
- Simulating water behavior on heated sinusoidally grooved surfaces.
- Analyzing nanoscale effects of surface topography and wettability.
Main Results:
- Increased surface roughness reduced bubble characteristic times (nucleation, growth, departure).
- Hydrophilic surfaces exhibited shorter bubble characteristic times than hydrophobic surfaces.
- Combined surface roughness and hydrophilicity synergistically accelerated bubble generation.
Conclusions:
- Surface roughness and hydrophilicity are critical parameters for enhancing nucleate boiling.
- Optimized surface properties can lead to significant improvements in heat transfer efficiency.
- Findings offer guidance for designing advanced heat exchangers and electronic cooling systems.
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