Lift enhancement by dynamically changing wingspan in forward flapping flight

  title={Lift enhancement by dynamically changing wingspan in forward flapping flight},
  author={Shizhao Wang and Xing Zhang and Guowei He and Tianshu Liu},
  journal={Physics of Fluids},
Dynamically stretching and retracting wingspan has been widely observed in the flight of birds and bats, and its effects on the aerodynamic performance particularly lift generation are intriguing. The rectangular flat-plate flapping wing with a sinusoidally stretching and retracting wingspan is proposed as a simple model for biologically inspired dynamic morphing wings. Numerical simulations of the low-Reynolds-number flows around the flapping morphing wing are conducted in a parametric space… 

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  • Engineering, Physics
    The Journal of experimental biology
  • 2002
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  • 2004
Man manipulation of the translational and rotational aerodynamic mechanisms may provide a potent means by which a flying animal can modulate direction and magnitude of flight forces for manoeuvring flight control and steering behaviour.

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INSECTS cannot fly, according to the conventional laws of aerodynamics: during flapping flight, their wings produce more lift than during steady motion at the same velocities and angles of attack1–5.

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  • S. Sane
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    Journal of Experimental Biology
  • 2003
The basic physical principles underlying flapping flight in insects, results of recent experiments concerning the aerodynamics of insect flight, as well as the different approaches used to model these phenomena are reviewed.

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