Very small insects use novel wing flapping and drag principle to generate the weight-supporting vertical force

  title={Very small insects use novel wing flapping and drag principle to generate the weight-supporting vertical force},
  author={Xin Cheng and Mao Sun},
  journal={Journal of Fluid Mechanics},
  pages={646 - 670}
  • Xin ChengM. Sun
  • Published 15 July 2018
  • Engineering
  • Journal of Fluid Mechanics
The effect of air viscosity on the flow around an insect wing increases as insect size decreases. For the smallest insects (wing length $R$ below 1 mm), the viscous effect is so large that lift-generation mechanisms used by their larger counterparts become ineffective. How the weight-supporting vertical force is generated is unknown. To elucidate the aerodynamic mechanisms responsible, we measure the wing kinematics of the tiny wasp Encarsia formosa (0.6 mm $R$ ) in hovering or very slow… 

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