Recent studies have revealed that contact line forces play an important role in the droplet spreading process. Despite their significance, the physics related to them has been studied only indirectly and the effect of contact line forces is still being disputed. We performed a molecular dynamics simulation and mimicked the droplet spreading process at the nanoscale. Based on the results of the simulation, the contact line forces were directly calculated. We found that the forces acting on the bulk and the contact line region showed different trends. Distinct positive and negative forces, contact line spreading, and friction forces were observed near the contact line. We also observed a strong dependency of the atomic kinetics in the contact line region on the variations in the contact line forces. The atoms of the liquid in the contact line region lost their kinetic energy due to the contact line friction force and became partially immobile on the solid surface. The results of the current study will be useful for understanding the role of the contact line forces on the kinetic energy dissipation in the contact line region.
Bibliographical noteFunding Information:
This work was supported by the Advanced Research Center Program (NRF-2015R1A5A1037668) through a National Research Foundation of Korea (NRF) grant funded by the Ministry of Science, ICT, and Future Planning (MSIP).
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Physics and Astronomy(all)
- Surfaces and Interfaces
- Surfaces, Coatings and Films