A universal three-dimensional instability of the wakes of two-dimensional bluff bodies

@article{Rao2016AUT,
  title={A universal three-dimensional instability of the wakes of two-dimensional bluff bodies},
  author={Anirudh Narayan Rao and Mark Christopher Thompson and Kerry Hourigan},
  journal={Journal of Fluid Mechanics},
  year={2016},
  volume={792},
  pages={50 - 66}
}
Linear stability analysis of a wide range of two-dimensional and axisymmetric bluff-body wakes shows that the first three-dimensional mode to became unstable is always mode E. From the studies presented in this paper, it is speculated to be the universal primary 3D instability, irrespective of the flow configuration. However, since it is a transition from a steady two-dimensional flow, whether this mode can be observed in practice does depend on the nature of the flow set-up. For example, the… 

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