Experiments in Fluids

, Volume 50, Issue 5, pp 1285–1292

Dual leading-edge vortex structure for flow over a simplified butterfly model

Research Article

Abstract

The dye visualization experiments show that a dual leading-edge vortex (LEV) structure exists on the suction side of a simplified butterfly model of Papilio ulysses at α = 8°−12°. Furthermore, the results of particle image velocimetry (PIV) measurement indicate that the axial velocity of the primary (outer) vortex core reaches the lower extreme value while a transition from a “wake-like” to a “jet-like” axial velocity profile occurs. The work reveals for the first time the existence of dual LEV structure on the butterfly-like forward-sweep wing configuration.

Abbreviations

c

Maximum chord length

d

Distance from X′–Z′ coordinates plane to the left apex of the model

L

Maximum span length

LEV

Leading-edge vortex

MAVs

Micro air vehicles

PIV

Particle image velocimetry

Re

Reynolds number

S

Span of the X′–Z′ coordinates plane over the left forewing of the model

U

Free-stream velocity

Ucore

Mean axial velocity

WTV

Wing-tip vortex

XY

Coordinates plane of the top view

X′–Z

Coordinates plane of the section view

α

Angle of attack

β

Angle of sideslip

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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  1. 1.Institute of Fluid Mechanics, Fluid Mechanics Key Laboratory of Education MinistryBeijing University of Aeronautics and AstronauticsBeijingPeople’s Republic of China

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