Evolution and breakdown of helical vortex wakes behind a wind turbine

The Science of Making Torque from Wind 2012

Nemes, A.^1 ; Sherry, M.^1 ; Lo Jacono, D.^1,2,3 ; Blackburn, H.M.^4 ; Sheridan, J.^1

Fluids Laboratory for Aeronautical and Industrial Research (FLAIR), Department of Mechanical and Aerospace Engineering, Monash University, Melbourne

VIC

3800, Australia^1

Université de Toulouse, INPT, IMFT, Allée Camille Soula, Toulouse

F-31400, France^2

CNRS, IMFT, Toulouse

F-31400, France^3

Department of Mechanical and Aerospace Engineering, Monash University, Melbourne

VIC

3800, Australia^4

关键词: Coherent structure;    Helical filament;    Helical vortices;    Particle image velocimetries;    Phase-locked average;    Proper orthogonal decompositions;    Tip vortex interactions;    Vortex identifications;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/555/1/012077/pdf
DOI  :  10.1088/1742-6596/555/1/012077

来源: IOP

【 摘 要 】

The wake behind a three-bladed Glauert model rotor in a water channel was investigated. Planar particle image velocimetry was used to measure the velocity fields on the wake centre-line, with snapshots phase-locked to blade position of the rotor. Phase- locked averages of the velocity and vorticity fields are shown, with tip vortex interaction and entanglement of the helical filaments elucidated. Proper orthogonal decomposition and topology-based vortex identification are used to filter the PIV images for coherent structures and locate vortex cores. Application of these methods to the instantaneous data reveals unsteady behaviour of the helical filaments that is statistically quantifiable.