Auralization of Wind Turbine Noise: Emission Synthesis

作者：Pieren Reto^*; Heutschi Kurt; Mueller Menno; Manyoky Madeleine; Eggenschwiler Kurt

来源：Acta Acustica United with Acustica, 2014, 100(1): 25-33.

DOI：10.3813/AAA.918683

An auralizator for wind turbine noise consists of an emission synthesizer, a propagation filter, a vegetation noise synthesizer and a suitable reproduction system. This article describes the synthesis of wind turbine sounds, considering spectral content and frequency dependent amplitude modulation (AM). The generated sound pressure signal is composed of discrete tonal components and amplitude modulated broadband noise, whereas the latter is processed in 1/3 octave bands. For each band, level fluctuations are synthesized as the superposition of a random process and a periodic function with the blade passing frequency. The model uses around 120 low-precision input parameters which are obtained by signal analysis of audio recordings. The separation of the stochastic and the periodic part of the level fluctuations is performed by using the autocorrelation function. The stochastic level fluctuations are further investigated by making use of the cross-correlation function. In this article the signal analysis algorithms and the synthesis model are exemplarily applied to recordings from two modern 2 MW turbines. The original and the synthesized sounds are provided. The quite complex wind turbine sound can be decomposed into only a few components that can be described by few parameters. As demonstrated by a listening test, the reconstruction of the wind turbine audio signal can be easily confused with the original sound.

• 出版日期2014-2