Effect of a surface tension gradient on the slip flow along a superhydrophobic air-water interface

@article{Song2018EffectOA,
  title={Effect of a surface tension gradient on the slip flow along a superhydrophobic air-water interface},
  author={Dong Song and Baowei Song and Hai-bao Hu and XiaoSong Du and Peng Du and Chang‐Hwan Choi and Jonathan P. Rothstein},
  journal={arXiv: Fluid Dynamics},
  year={2018},
  volume={3},
  pages={033303}
}
Superhydrophobic surfaces have been shown to produce significant drag reduction in both laminar and turbulent flows by introducing an apparent slip velocity along an air-water interface trapped within the surface roughness. In the experiments presented within this study, we demonstrate the existence of a surface tension gradient associated with the resultant Marangoni flow along an air-water interface that causes the slip velocity and slip length to be significantly reduced. In this study, the… 

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