TY - GEN
T1 - Infrasound and Low-Frequency Noise from Wind Turbines
AU - Hansen, Colin
AU - Zajamsek, Branko
AU - Hansen, Kristy
PY - 2016
Y1 - 2016
N2 - Infrasound, low-frequency noise (ILFN) and amplitude modulation of the noise are known to disturb some residents living near wind farms. However, the mechanisms responsible for ILFN and amplitude modulation are not well understood. In an attempt to shed some light on these mechanisms, acoustic measurements were taken close to a wind farm, at residences located two or more kilometres from the nearest turbine in a wind farm and in an anechoic chamber using a scale-model, electrically-driven, wind turbine. The measured spectra reveal distinct peaks at the frequencies corresponding to the blade-pass frequency and its harmonics, and the characteristics of these peaks are remarkably similar for field and laboratory measurements, indicating that the zero mean flow simulation is a good representation of an actual wind turbine. Near field acoustic holography measurements on the scalemodel turbine confirm that tonal components at the frequencies corresponding to the blade-pass frequency and its harmonics are generated as a result of blade-tower interaction, suggesting that it is likely to be an important mechanism of infrasound generation for industrial wind turbines. Inaccuracies in the assumed location of sources of noise generated by a wind turbine affect the accuracy of community noise predictions. This is because the source height affects the distance from the turbine beyond which sound rays arrive at the receiver having been reflected from the ground more than once, thus reducing the attenuation with distance from the turbine.
AB - Infrasound, low-frequency noise (ILFN) and amplitude modulation of the noise are known to disturb some residents living near wind farms. However, the mechanisms responsible for ILFN and amplitude modulation are not well understood. In an attempt to shed some light on these mechanisms, acoustic measurements were taken close to a wind farm, at residences located two or more kilometres from the nearest turbine in a wind farm and in an anechoic chamber using a scale-model, electrically-driven, wind turbine. The measured spectra reveal distinct peaks at the frequencies corresponding to the blade-pass frequency and its harmonics, and the characteristics of these peaks are remarkably similar for field and laboratory measurements, indicating that the zero mean flow simulation is a good representation of an actual wind turbine. Near field acoustic holography measurements on the scalemodel turbine confirm that tonal components at the frequencies corresponding to the blade-pass frequency and its harmonics are generated as a result of blade-tower interaction, suggesting that it is likely to be an important mechanism of infrasound generation for industrial wind turbines. Inaccuracies in the assumed location of sources of noise generated by a wind turbine affect the accuracy of community noise predictions. This is because the source height affects the distance from the turbine beyond which sound rays arrive at the receiver having been reflected from the ground more than once, thus reducing the attenuation with distance from the turbine.
UR - http://www.scopus.com/inward/record.url?scp=85019726310&partnerID=8YFLogxK
U2 - 10.1007/978-3-662-48868-3_1
DO - 10.1007/978-3-662-48868-3_1
M3 - Conference contribution
SN - 9783662488669
T3 - Lecture Notes in Mechanical Engineering
SP - 3
EP - 16
BT - Fluid-Structure-Sound Interactions and Control: Proceedings of the 3rd Symposium on Fluid-Structure_Sound Interactions and Control
A2 - Zhou, Yu
A2 - Lucey, A.D.
A2 - Liu, Yang
A2 - Huang, Lixi
PB - Springer
ER -