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Slip transition in dynamic wetting for a generalized Navier boundary condition
Valentin Rougier1, Julien Cellier2, Moussa Gomina2
1CRISMAT, UMR 6508 CNRS, ENSICAEN, 6 Boulevard Maréchal Juin, 14050 Caen Cedex 4, France; LOMC, UMR 6294 Université du Havre, 53 rue de Prony, 76058 Le Havre, France.
Journal of Colloid and Interface Science
|October 5, 2020
Summary
This study quantifies the relationship between contact-line velocity and slip length in dynamic wetting simulations using the generalized Navier boundary condition (GNBC). Results show a clear transition, bridging molecular and continuum scales in fluid dynamics.
Area of Science:
- Fluid dynamics
- Materials science
- Surface science
Background:
- Dynamic wetting simulations often use slip models.
- The generalized Navier boundary condition (GNBC) offers potential for bridging molecular and continuum scales.
- Quantitative experimental comparisons for GNBC are lacking.
Purpose of the Study:
- Investigate the dependence between contact-line velocity and slip length in GNBC.
- Compare numerical simulations with experimental data for dynamic wetting.
- Validate GNBC for fluid dynamics simulations.
Main Methods:
- Assessed physical properties of polyethylene glycol.
- Measured dynamic contact angle on a cellulosic substrate using the Wilhelmy method.
- Reproduced experiments in a finite elements model with GNBC for various capillary numbers and slip lengths.
Main Results:
- Selected realistic slip length by matching simulated and experimental dynamic contact angles.
- Observed a clear transition in slip length behavior with contact line velocity.
- Reproduced dynamic wetting transition between frictional and viscous dissipations.
Conclusions:
- GNBC provides a quantitative link between contact-line velocity and slip length.
- The model successfully reproduces dynamic wetting transitions.
- Findings contribute to bridging the gap between molecular and continuum scales in fluid dynamics.
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