Resource Documents by Zajamšek, Branko

Nguyen, Phuc; Hansen, Kristy; Lechat, Bastien; Catcheside, Peter; Zajamsek, Branko; and Hansen, Colin
Benchmark characterisation and automated detection of wind farm noise amplitude modulation 
[Abstract] Amplitude modulation (AM) is a characteristic feature of wind farm noise and has the potential to contribute to annoyance and sleep disturbance. Detection, quantification and characterisation of AM is relevant for regulatory bodies that seek to reduce adverse impacts of wind farm noise and for researchers and wind farm developers that aim to understand and account for this phenomenon. We here present an approach to detect and characterise AM in a comprehensive and long-term wind farm noise data set . . . Complete article »

Nguyen, Phuc; Hansen, Kristy; Catcheside, Peter; Hansen, Colin; and Zajamsek, Branko
Long-term quantification and characterisation of wind farm noise amplitude modulation 
[Abstract] The large-scale expansion of wind farms has prompted community debate regarding adverse impacts of wind farm noise (WFN). One of the most annoying and potentially sleep disturbing components of WFN is amplitude modulation (AM). Here we quantified and characterised AM over one year using acoustical and meteorological data measured at three locations near three wind farms. We found that the diurnal variation of outdoor AM prevalence was substantial, whereby the nighttime prevalence was approximately 2 to 5 times higher . . . Complete article »

Nguyen, Phuc; Hansen, Kristy; Zajamšek, Branko; and Catcheside, Peter
Evaluation of wind farm noise amplitude modulation synthesis quality 
Abstract – Wind farm noise amplitude modulation (WFNAM) is a major contributor to annoyance and could cause sleep disturbance. In laboratory listening experiments assessing its annoyance and sleep disturbance potential, WFNAM stimuli are commonly synthesised and can thus suffer from a lack of ecological validity. Here, five stimuli synthesis methods were compared with measured noise in terms of their perceived similarity. An ABX discrimination listening test and one-third octave band spectra were used for evaluation of the aural and visual similarity, . . . Complete article »

Hansen, Kristy; Nguyen, Phuc; Zajamšek, Branko; Catcheside, Peter; and Hansen, Colin
Prevalence of wind farm amplitude modulation at long-range residential locations 
ABSTRACT – The presence of amplitude modulation (AM) in wind farm noise has been shown to result in increased annoyance. Therefore, it is important to determine how often this characteristic is present at residential locations near a wind farm. This study investigates the prevalence and characteristics of wind farm AM at 9 different residences located near a South Australian wind farm that has been the subject of complaints from local residents. It is shown that an audible indoor low-frequency tone was . . . Complete article »

Hansen, Kristy; Nguyen, Phuc; Zajamšek, Branko; Micic, Gorica; and Catcheside, Peter
Pilot study on perceived sleep acceptability of low-frequency, amplitude modulated tonal noise 
Abstract— The global expansion of wind farm facilities has been associated with community complaints regarding sleep disturbance. This may be related to the presence of amplitude modulation (AM) in wind turbine noise (WTN), which has been shown to result in increased annoyance. However, at present, it is unknown whether acceptability for sleep is judged differently to annoyance or if AM may be more problematic for sleep than other noise types. Previous studies have also focused predominantly on ‘swish’ noise rather . . . Complete article »

Hansen, Kristy; Zajamšek, Branko; and Hansen, Colin
Investigation of a microphone height correction for long-range wind farm noise measurements 
Abstract: In the measurement of wind farm noise, it is standard practice to mount outdoor microphones at a height of 1.5 m. On the other hand, measurements at this height can be affected by wind-induced noise, which has the potential to mask the noise of interest, particularly at low and infrasonic frequencies. Therefore, to minimise wind-induced noise, it is advantageous to measure on or below the ground, where the wind speed is close to zero. However, results from measurements taken at . . . Complete article »

Zajamšek, Branko; et al.
Experimental and numerical investigation of blade–tower interaction noise 
Abstract: This paper describes the generation of blade–tower interaction (BTI) noise from upwind turbines and pylon-mounted fans using a combination of experimental and numerical means. An experimental rotor-rig was used in an anechoic chamber to obtain BTI acoustic data under controlled conditions. A computational model, based on the solution of the unsteady Reynolds Averaged Navier Stokes (URANS) equations and Curle’s acoustic analogy, was used to describe the generation of fan and simplistic model of wind turbine BTI noise by the . . . Complete article »

Hansen, Kristy; Nguyen, Phuc; Zajamšek, Branko; Catcheside, Peter; and Hansen, Colin
Prevalence of wind farm amplitude modulation at long-range residential locations 
Abstract: The presence of amplitude modulation (AM) in wind farm noise has been shown to result in increased annoyance. Therefore, it is important to determine how often this characteristic is present at residential locations near a wind farm. This study investigates the prevalence and characteristics of wind farm AM at 9 different residences located near a South Australian wind farm that has been the subject of complaints from local residents. It is shown that an audible indoor low-frequency tone was . . . Complete article »

Nguyen, Phuc; Hansen, Kristy; and Zajamšek, Branko
Characterizing tonal amplitude modulation of wind farm noise 
[ABSTRACT] In addition to the overall noise level, periodic variations in the loudness of wind turbine noise, known as Amplitude Modulation (AM), also significantly contribute to the annoyance experienced by residents living near wind farms. Due to the high dependence of AM on meteorological conditions and the type of wind turbines, the level and duration of AM are hard to predict. These characteristics have an important impact on the annoyance response of residents. The level of annoyance is expected to . . . Complete article »

Zajamšek, Branko; Hansen, Kristy; Doolan, Con; and Hansen, Colin
Characterisation of wind farm infrasound and low-frequency noise 
This paper seeks to characterise infrasound and low-frequency noise (ILFN) from a wind farm, which contains distinct tonal components with distinguishable blade-pass frequency and higher harmonics. Acoustic measurements were conducted at dwellings in the vicinity of the wind farm and meteorological measurements were taken at the wind farm location and dwellings. Wind farm ILFN was measured frequently under stable and very stable atmospheric conditions and was also found to be dependent on the time of year. For noise character assessment, . . . Complete article »

Hansen, Kristy; Zajamšek, Branko; and Hansen, Colin
Comparison of the noise levels measured in the vicinity of a wind farm for shutdown and operational conditions 
ABSTRACT Outdoor and indoor microphone measurements have been taken in the vicinity of the Waterloo wind farm at a number of locations during periods when the nearby wind farm was operational as well as when it was shutdown. The majority of the shutdowns were of short duration and deliberate on the part of the wind farm operator, as they were associated with the recent EPA noise impact study. However, one of the shutdowns lasted for several days as it was . . . Complete article »

Zajamšek, Branko; Hansen, Kristy; and Hansen, Colin
Investigation of the time-dependent nature of infrasound measured near a wind farm 
ABSTRACT It is well-known that wind farm noise is dominated by low-frequency energy at large distances from the wind farm, where the high frequency noise has been more attenuated than low-frequency noise. It has also been found that wind farm noise is highly variable with time due to the influence of atmospheric factors such as atmospheric turbulence, wake turbulence from upstream turbines and wind shear, as well as effects that can be attributed to blade rotation. Nevertheless, many standards that . . . Complete article »

Zajamšek, Branko; Moreau, Danielle; Doolan, Con; and Hansen, Kristy
Indoor Infrasound and low-frequency noise monitoring in a rural environment 
This paper presents the results of recent indoor noise monitoring test that was conducted in a room of a home near a wind farm whose resident claims to be annoyed by wind farm noise. The testing uses low-frequency microphones that can resolve noise below 0.5 Hz. The aim of the study is to examine the relationship(s) between the sound pressure level, weather conditions, resident rated annoyance to sound and wind farm output power data. The study concentrates on sound in . . . Complete article »

Also try:
Search all of documents for "Zajamšek, Branko".
Search entire site for "Zajamšek, Branko".