Superfluid Boundary Layer.

  title={Superfluid Boundary Layer.},
  author={George W. Stagg and Nick G. Parker and Carlo F. Barenghi},
  journal={Physical review letters},
  volume={118 13},
We model the superfluid flow of liquid helium over the rough surface of a wire (used to experimentally generate turbulence) profiled by atomic force microscopy. Numerical simulations of the Gross-Pitaevskii equation reveal that the sharpest features in the surface induce vortex nucleation both intrinsically (due to the raised local fluid velocity) and extrinsically (providing pinning sites to vortex lines aligned with the flow). Vortex interactions and reconnections contribute to form a dense… 

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