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Title:
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Acoustic noise measurements on wind turbines: carried out in theframework of JOULE programme (contract nr. JOU2-CT92-0124) [ECN-C-
-94-109]
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Author(s):
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Published by:
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Publication date:
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ECN
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1995
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ECN report number:
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Document type:
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ECN-C--94-109
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ECN publication
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Number of pages:
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Full text:
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50
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Download PDF
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Abstract:
The individual differences in the acoustic properties of nominallyidentical wind turbines have been quantified by measurements on two series of
five turbines of equal make and model. The results show that the differences
in the sound power levels of nominally identical wind turbines are
characterised by a standard deviation of 1.1 to 1.3 dB. The differences in
tonality show that the result of a tonality assessment on a turbine give no
reliable information on the tonality of another turbine of the same series.
The reproducibility of the measured properties of a turbine has been
quantified by five repeated measurements on one turbine in a period of 5
months. The variations in the measured sound power levels, due to the
combination of the instability of the turbine and the uncertainty in the
measurements, is characterised by a standard deviation of 0.3 dB. The
measurements showed that the tonality of the turbine is not stable in time.
30 figs., 2 tabs., 1 ref.
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