Ceranna Et Al, The Inaudible Noise of Wind Turbines – Infrasound

Lars Ceranna, Gernot Hartmann, Manfred Henger,
Federal Institute for Geosciences and Natural Resources, Hannover, Germany
Presented at the Infrasound Workshop November 28 – December 02, 2005, Tahiti

  • The number of wind turbines and their size is constantly growing
  • wind turbines and wind farms generate strong infrasonic noise which is characterized by their blade passing harmonics (monochromatic signals)
  • generated noise of wind turbines can theoretically be estimated
    ● geometrical spreading ~ R-1
    ● SPL ~ rpm4
  • recordings from field measurements near a single wind turbine show that the theoretical model is also valid for frequencies below a few Hz
  • minimum distance between an infrasound array and a wind farm can be estimated to avoid reduction of the array’s detection capability (e.g. 600MW wind turbine: d>15 km, 11-element wind farm: d>30 km)

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