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Experiments in Fluids

, 54:1417 | Cite as

Characterisation of a horizontal axis wind turbine’s tip and root vortices

  • Michael Sherry
  • John Sheridan
  • David Lo Jacono
Research Article

Abstract

The vortical near wake of a model horizontal axis wind turbine has been investigated experimentally in a water channel. The objective of this work is to study vortex interaction and stability of the helical vortex filaments within a horizontal axis wind turbine wake. The experimental model is a geometrically scaled version of the Tjæreborg wind turbine, which existed in western Denmark in the late 1980s. Here, the turbine was tested in both the upwind and downwind configurations. Qualitative flow visualisations using hydrogen bubble, particle streakline and planar laser-induced fluorescence techniques were combined with quantitative data measurements taken using planar particle image velocimetry. Vortices were identified using velocity gradient tensor invariants. Parameters that describe the helical vortex wake, such as the helicoidal pitch, and vortex circulation, were determined for three tip speed ratios. Particular attention is given here to the root vortex, which has been investigated minimally to date. Signatures of the coherent tip vortices are seen throughout the measurement domain; however, the signature of the root vortex is only evident much closer to the rotor plane, irrespective of the turbine configuration. It is postulated that the root vortex diffuses rapidly due to the effects of the turbine support geometries.

Keywords

Vortex Wind Turbine Separate Shear Layer Laminar Separation Bubble Horizontal Axis Wind Turbine 
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 Berlin Heidelberg 2013

Authors and Affiliations

  • Michael Sherry
    • 1
  • John Sheridan
    • 1
  • David Lo Jacono
    • 1
    • 2
    • 3
  1. 1.Fluids Laboratory for Aeronautical and Industrial Research (FLAIR), Department of Mechanical and Aerospace EngineeringMonash UniversityMelbourneAustralia
  2. 2.INPT, UPS, IMFT (Institut de Mécanique des Fluides de Toulouse)Université de ToulouseToulouseFrance
  3. 3.CNRS, IMFTToulouseFrance

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