Molecular Origin of Contact Line Friction in Dynamic Wetting

  title={Molecular Origin of Contact Line Friction in Dynamic Wetting},
  author={Petter Johansson and Berk Hess Kth Royal Institute of Technology and Stockholm and Sweden.},
  journal={arXiv: Fluid Dynamics},
A hydrophilic liquid, such as water, forms hydrogen bonds with a hydrophilic substrate. The strength and locality of the hydrogen bonding interactions prohibit slip of the liquid over the substrate. The question then arises how the contact line can advance during wetting. Using large-scale molecular dynamics simulations we show that the contact line advances by single molecules moving ahead of the contact line through two distinct processes: either moving over or displacing other liquid… Expand

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