Turbulence Distortion Effect on Leading Edge Noise from Wind Turbine Blades

Authors

  • Vasishta Bhargava Nukala GITAM (Deemed to be) University Department of mechanical engineering, School of Technology, Patancheru, Telangana, IN
  • Chinmaya Prasad Padhy GITAM (Deemed to be) University, School of Technology, Patancheru, Telangana, IN

Abstract

Turbulence distortion is a potential source for production of flow induced noise and rely on the turbulence properties of aerodynamic flow field. Particularly in wind energy applications, the broadband leading-edge noise from rotating blades becomes significant when the turbulence intensity (TI) and integral length scale factors vary with mean flow velocity and rms velocity fluctuations. The inflow noise generated at leading edge of blade also varies significantly with turbulence characteristics of velocity spectrum that describes the turbulent kinetic energy envelope. Although previous studies on flow induced noise that includes turbulence distortion have accounted for symmetric and cambered airfoils, it has not been investigated for rotating blades as found in wind turbines. In this work, leading edge noise predicted by modified rapid turbulence distortion (RDT) model proposed by Faria et al (2022) is applied and compared with noise levels predicted by Moriarty model for a 2MW model wind turbine blade. For low frequencies in sound spectra, 50Hz < f < 200Hz the sound power predicted by both models agreed within 2-5% with experiment data of a SWT 2.3MW wind turbine blade which has tip speed of ~83 m/s. However, for mid-band frequencies 250Hz < f < 1kHz, the modified rapid distortion model scales the turbulence properties in velocity spectrum more accurately leading to better estimation of noise levels. The modified RDT model has also been tested for different turbulence intensities and found that as turbulence intensity increased, the standard error for noise predicted by modified RDT model reduced by 1% in low frequency region of sound spectrum. This trend is not observed in case of Moriarty model and on contrary noise levels were found to increase.

Additional Files

Published

2023-10-09

How to Cite

1.
Nukala VB, Padhy CP. Turbulence Distortion Effect on Leading Edge Noise from Wind Turbine Blades. Canadian Acoustics [Internet]. 2023 Oct. 9 [cited 2024 May 22];51(3):42-3. Available from: https://jcaa.caa-aca.ca/index.php/jcaa/article/view/4023

Issue

Section

Proceedings of the Acoustics Week in Canada