Fast-swimming hydromedusae exploit velar kinematics to form an optimal vortex wake

@article{Dabiri2006FastswimmingHE,
  title={Fast-swimming hydromedusae exploit velar kinematics to form an optimal vortex wake},
  author={John O. Dabiri and Sean P. Colin and John H. Costello},
  journal={Journal of Experimental Biology},
  year={2006},
  volume={209},
  pages={2025 - 2033}
}
SUMMARY Fast-swimming hydromedusan jellyfish possess a characteristic funnel-shaped velum at the exit of their oral cavity that interacts with the pulsed jets of water ejected during swimming motions. It has been previously assumed that the velum primarily serves to augment swimming thrust by constricting the ejected flow in order to produce higher jet velocities. This paper presents high-speed video and dye-flow visualizations of free-swimming Nemopsis bachei hydromedusae, which instead… 
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