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Experiments in Fluids

, Volume 15, Issue 3, pp 159–167 | Cite as

Laser-scanning particle image velocimetry applied to a delta wing in transient maneuver

  • C. Magness
  • O. Robinson
  • D. Rockwell
Originals

Abstract

A laser scanning technique, which utilizes a galvanometer scanner to produce particle-image photographs, is employed to investigate the flow over a delta wing undergoing pitching maneuvers at a high angle of attack. Use of a unique forcing system and a large-scale prism arrangement allow characterization of the instantaneous velocity field over the entire crossflow plane at a desired angle of attack.

Contours of constant streamwise vorticity are calculated from the crossflow velocity field at various pitching rates. The vorticity distribution occurring during the pitch-up motion differs substantially from that on the stationary wing at the same angle of attack. During the pitch-up motion, the leading-edge vortex is remarkably coherent, in contrast to the disordered structure on the stationary wing. During the corresponding pitch-down motion, the vorticity distribution is quite similar to that on the stationary wing at the same angle of attack. This behavior is evident for a range of pitching rates.

Keywords

Vortex Vorticity Particle Image Velocimetry Velocimetry Instantaneous Velocity 
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.

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Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • C. Magness
    • 1
  • O. Robinson
    • 1
  • D. Rockwell
    • 1
  1. 1.Department of Mechanical Engineering and MechanicsLehigh UniversityBethlehemUSA

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