Lift enhancement by dynamically changing wingspan in forward flapping flight

@article{Wang2014LiftEB,
  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},
  year={2014},
  volume={26},
  pages={061903}
}
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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