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Experiments in Fluids

, Volume 46, Issue 5, pp 823–833 | Cite as

The influence of airfoil kinematics on the formation of leading-edge vortices in bio-inspired flight

  • David Rival
  • Tim Prangemeier
  • Cameron Tropea
Research Article

Abstract

The formation process of leading-edge vortices has been investigated experimentally using Particle Image Velocimetry. Various airfoil kinematics have been tested, including asymmetric and peak-shifted plunging motions, and are evaluated for Re = 30,000 and a reduced frequency range of 0.2 ≤ k ≤ 0.33. By measuring the growth in the leading-edge vortex during the dynamic-stall process, the vortex pinch-off process is examined based on the concept of an optimal vortex formation time. The various kinematics are then evaluated with respect to their associated vortex strength, timing and convection into the wake.

Keywords

Vortex Particle Image Velocimetry Vortex Pair Sinusoidal Motion Effective Angle 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

The authors would like to thank Dr. Michael Ol from Wright-Patterson AFB for the fruitful discussions regarding Theodorsen’s theory. This research was supported by the Deutsche Forschungsgemeinschaft (DFG) within the national priority program entitled Nature-Inspired Fluid Mechanics (SPP1207).

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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  1. 1.Institute of Fluid Mechanics and AerodynamicsTechnische Universität DarmstadtDarmstadtGermany

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