Unsteady nature of vortex pair in formation flight

Research output: Contribution to conferencePaper

Abstract

The interaction of trailing vortices from a leading wing with rigid and flexible downstream wings has been investigated experimentally in an open jet wind tunnel using force measurements, particle image velocimetry measurements, hotwire measurements and deformation measurements. Counter-rotating leading vortex has been found to have substantial meandering when it is close to the tip of the downstream wing. The leading vortex forms a pair with the vortex from the downstream wing, and then exhibits large displacements around the wing tip. This has been found to cause the largest lift fluctuations on the downstream wing. The meandering of the vortex pair occurs at the natural meandering frequency of the isolated vortex, with a low Strouhal number, and is not affected by the frequency of the wing bending oscillations if the downstream wing is flexible. While the displacement of the leading vortex is larger than that of the trailing vortex, time-dependent variations of the core radius, core vorticity and circulation are evident for the trailing vortex. In contrast, co-rotating vortices do not exhibit any increased meandering.

Original languageEnglish
DOIs
Publication statusPublished - 2017
Event47th AIAA Fluid Dynamics Conference, 2017 - Denver, USA United States
Duration: 5 Jun 20179 Jun 2017

Conference

Conference47th AIAA Fluid Dynamics Conference, 2017
CountryUSA United States
CityDenver
Period5/06/179/06/17

Fingerprint

Vortex flow
Flexible wings
Strouhal number
Force measurement
Vorticity
Velocity measurement
Wind tunnels
Natural frequencies

ASJC Scopus subject areas

  • Aerospace Engineering
  • Engineering (miscellaneous)

Cite this

Chen, C., Wang, Z., & Gursul, I. (2017). Unsteady nature of vortex pair in formation flight. Paper presented at 47th AIAA Fluid Dynamics Conference, 2017, Denver, USA United States. https://doi.org/10.2514/6.2017-3306

Unsteady nature of vortex pair in formation flight. / Chen, C.; Wang, Z.; Gursul, Ismet.

2017. Paper presented at 47th AIAA Fluid Dynamics Conference, 2017, Denver, USA United States.

Research output: Contribution to conferencePaper

Chen, C, Wang, Z & Gursul, I 2017, 'Unsteady nature of vortex pair in formation flight' Paper presented at 47th AIAA Fluid Dynamics Conference, 2017, Denver, USA United States, 5/06/17 - 9/06/17, . https://doi.org/10.2514/6.2017-3306
Chen C, Wang Z, Gursul I. Unsteady nature of vortex pair in formation flight. 2017. Paper presented at 47th AIAA Fluid Dynamics Conference, 2017, Denver, USA United States. https://doi.org/10.2514/6.2017-3306
Chen, C. ; Wang, Z. ; Gursul, Ismet. / Unsteady nature of vortex pair in formation flight. Paper presented at 47th AIAA Fluid Dynamics Conference, 2017, Denver, USA United States.
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