Three-Dimensional Aerodynamics and Vortex-Shedding Characteristics of Wind Turbine Airfoils Over 360-Degree Angles of Attack: Article No. 4328

Research output: Contribution to journalArticlepeer-review

Abstract

In this work, we present the first three-dimensional (3D) computational investigation of wind turbine airfoils over 360 degrees angles of attack to predict unsteady aerodynamic loads and vortex-shedding characteristics. To this end, static-airfoil simulations are performed for the FFA-W3 airfoil family at a Reynolds number of 107 with the Improved Delayed Detached Eddy Simulation turbulence model. Aerodynamic forces reveal that the onset of boundary-layer instabilities and flow separation does not necessarily coincide with the onset of stall. In addition, a comparison with two-dimensional simulation data and flat plate theory extension of airfoil polars, suggest that, in the deep stall regime, 3D effects remain critical for predicting both the unsteady loads and the vortex-shedding dynamics. For all airfoils, the vortex-shedding frequencies are found to be inversely proportional to the wake width. In the case of slender airfoils, the frequencies are nearly independent of the airfoil thickness, and their corresponding Strouhal number St is approximately 0.15. Based on the calculated St, the potential for shedding frequencies to coincide with the natural frequencies of the International Energy Agency 15 MW reference wind turbine blades is investigated. The analysis shows that vortex-induced vibrations occur primarily at angles of attack of around +-90 degrees for all airfoils.
Original languageAmerican English
Number of pages24
JournalEnergies
Volume17
Issue number17
DOIs
StatePublished - 2024

NREL Publication Number

  • NREL/JA-5000-89901

Keywords

  • FFA-W3 airfoil
  • Improved Delayed Detached Eddy Simulation (IDDES)
  • Strouhal number
  • vortex-shedding frequency
  • wind turbine

Fingerprint

Dive into the research topics of 'Three-Dimensional Aerodynamics and Vortex-Shedding Characteristics of Wind Turbine Airfoils Over 360-Degree Angles of Attack: Article No. 4328'. Together they form a unique fingerprint.

Cite this