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Mathematical models for the van der Waals force and capillary force between a rough particle and surface
1School of Mechanical and Aerospace Engineering, Nanyang Technological University, 639798 Singapore.
Langmuir : the ACS Journal of Surfaces and Colloids
|June 28, 2013
Summary
Predicting adhesion forces between rough particles and surfaces is crucial. New fractal-based models accurately estimate van der Waals and capillary forces, aligning with experimental data and improving upon smooth surface models.
Area of Science:
- Surface science
- Materials science
- Physics
Background:
- Accurate prediction of adhesion forces (van der Waals, capillary) is vital for understanding particle retention and resuspension.
- Existing models often simplify surface roughness, limiting their applicability.
- Fractal theory offers a more comprehensive approach to describing multi-scale roughness.
Purpose of the Study:
- To develop novel mathematical models for predicting adhesion forces between rough particles and surfaces.
- To incorporate fractal theory and Gaussian roughness distribution into adhesion force calculations.
- To analyze the influence of various parameters on adhesion forces.
Main Methods:
- Development of mathematical models based on fractal theory and Gaussian roughness distribution.
- Validation of models against existing experimental data for van der Waals and capillary forces.
- Comparative analysis with classical smooth surface models and other existing studies.
Main Results:
- Proposed models demonstrate good agreement with experimental data.
- Models accurately predict the influence of surface roughness, relative humidity (RH), contact angle, and Hurst exponent on adhesion forces.
- Adhesion force decline with roughness/contact angle and increase with RH/Hurst exponent are well-predicted.
Conclusions:
- The developed fractal-based models provide a robust framework for predicting adhesion forces on rough surfaces.
- These models offer improved accuracy and broader applicability compared to classical smooth surface models.
- The findings are significant for processes involving particle-surface interactions in various scientific and engineering fields.
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