Can vortex criteria be objectivized?

  title={Can vortex criteria be objectivized?},
  author={George Haller},
  journal={Journal of Fluid Mechanics},
  • G. Haller
  • Published 8 December 2020
  • Mathematics
  • Journal of Fluid Mechanics
Abstract Several procedures have been proposed to modify non-objective (observer-dependent) local vortex criteria so that they become objective. These modifications are only justifiable if they are equivalent to applying the original criteria after a generalized (possibly nonlinear) frame change is performed on the flow domain; otherwise, the arguments used in deriving those criteria no longer apply. To examine the feasibility of available objectivization procedures, we derive here necessary… Expand
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  • G. Haller
  • Physics
  • Journal of Fluid Mechanics
  • 2005
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