Complete measurement of helicity and its dynamics in vortex tubes

  title={Complete measurement of helicity and its dynamics in vortex tubes},
  author={Martin W Scheeler and Wim M. van Rees and Hridesh Kedia and Dustin Kleckner and William T. M. Irvine},
  pages={487 - 491}
Linking fluids as they twist and writhe Helicity is a measure of cork-screw-like motion described by the amount of twisting, writhing, and linking in a fluid. Total helicity is conserved for ideal fluids, but how helicity changes in real fluids with even tiny amounts of viscosity has been an open question. Scheeler et al. provide a complete measurement of total helicity in a real fluid by using a set of hydrofoils to track linking, twisting, and writhing (see the Perspective by Moffatt). They… Expand
Helicity—invariant even in a viscous fluid
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Velocity, energy, and helicity of vortex knots and unknots.
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  • Physics, Medicine
  • Proceedings of the National Academy of Sciences
  • 2014
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