Home Journal
E-mail Print
Acoustics Australia  Logo (3032 bytes)
Vol 40 No 1

CONTENTS

April 2012


ARTICLES

Wind turbine noise mechanisms and some concepts for its control
Con J. Doolan, Danielle J. Moreau and Laura A. Brooks
PDF Full Paper

On measuring and determining wind turbine noise emissions at distant sensitive receptor locations - a challenge
George F. Hessler Jr. and Paul D. Schomer
PDF Full Paper

Sources of wind turbine noise and sound propagation
Renzo Tonin
PDF Full Paper

Comparison of predicted and measured wind farm noise levels and implications for assessments of new wind farms
Tom Evans and Jonathan Cooper
PDF Full Paper

Comparison of compliance results obtained from the various wind farm standards used in Australia
Jonathan Cooper, Tom Evans and Luis Najera
PDF Full Paper

Measurement and level of infrasound from wind farms and other sources
Chris Turnbull, Jason Turner and Daniel Walsh
PDF Full Paper

Analysis techniques for wind farm sound level measurements
Michael Smith and Stephen Chiles
PDF Full Paper

TECHNICAL NOTES

The steep and the tearful - a New Zealand perspective of wind turbine noise
Stuart Camp
PDF Full Paper

Noise dose assessment of wind farm noise
Andy McKenzie
PDF Full Paper

Finding the character of wind turbine sound
Bob Thorne
PDF Full Paper

Low frequency, infrasound and amplitude modulation noise from wind farms - some recent findings
Colin Tickell
PDF Full Paper

Wind turbine syndrome - an alternative view
Dick Bowdler
PDF Full Paper

A review of the Draft NSW Planning Guidelines: Wind Farms
Justin Adcock, Christophe Delaire and Dan Griffin
PDF Full Paper

Development of the Draft NSW Planning Guidelines: Wind Farms
Jeff Parnell
PDF Full Paper

Book Reviews
News
New Products
Prizes & Awards
Obituary
Meeting Reports
Future Conference
Diary
Sustaining Members
Advertisers Index


Wind turbine noise mechanisms and some concepts for its control

Con J. Doolan, Danielle J. Moreau and Laura A. Brooks
School of Mechanical Engineering, The University of Adelaide, Adelaide, SA 5005, Australia

Vol. 40, No. 1 pp 7 - 13 (2012)
ABSTRACT: The aerodynamic noise production mechanisms of modern horizontal axis wind turbines are reviewed. An engineering analysis of the time and frequency scales from three noise sources, leading edge turbulence interaction noise, trailing edge noise and blade-tower interaction noise is presented. The analysis shows that noise sources are present from low-frequencies (1-4 Hz) to over 500 Hz for a representative wind turbine. The results of the analysis are used to explain amplitude modulation observed during noise measurements at a European wind farm. Daytime noise measurements close to a South Australian wind farm are also presented that show amplitude modulation. The paper concludes with a description of conceptual ideas for the control of wind turbine noise.

On measuring and determining wind turbine noise emissions at distant sensitive receptor locations - a challenge

George F. Hessler Jr. Hessler Associates, Inc., Haymarket, VA USA, This e-mail address is being protected from spambots. You need JavaScript enabled to view it
Paul D. Schomer Schomer and Associates, Inc., Champaign, ILL USA, This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Vol. 40, No. 1 pp 14 - 19 (2012)
ABSTRACT: Determining noise emissions attributable solely to wind turbine/s at potentially sensitive receptor locations far from the turbines is a technical challenge indeed. If the project is successfully designed acoustically, the wind turbine source is barely audible during the day or night with relatively moderate winds and not distinguishable at all during high winds. We must try to separate wind turbine emissions from the prevailing background environment and from sounds created by the same wind that drives the turbines. This paper suggests a methodology that measures surrounding turbine emissions simultaneously at the standard IEC-61400-11 distance to document background-free emissions for input into a relatively simple propagation model to calculate true turbine emissions at the distant receptor location of interest. An example is given from an actual site where turbine noise emissions could be accurately measured at the receptor location for comparison to model calculations.

Sources of wind turbine noise and sound propagation

Renzo Tonin
Renzo Tonin & Associates (NSW) Pty Ltd, PO Box 877, Strawberry Hills, NSW 2012 This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Vol. 40, No. 1 pp 20 - 27 (2012)
ABSTRACT: The mechanism of noise generation by wind turbines is a subject not yet fully understood. A large number of complex flow phenomena occur, each of which generate sound in particular frequency bands. The purpose of this paper is to provide a brief description of the current state of technology in respect of noise generation from a wind turbine in a complex meteorological atmosphere and reliable methods of noise prediction to sensitive receptors.

Comparison of predicted and measured wind farm noise levels and implications for assessments of new wind farms

Tom Evans1 and Jonathan Cooper2
1 AECOM, Level 28, 91 King William Street, Adelaide, SA 5000
2 Resonate Acoustics, 97 Carrington Street, Adelaide, SA 5000

Vol. 40, No. 1 pp 28 - 36 (2012)
ABSTRACT: To maximise the energy output of wind farms whilst still meeting the relevant noise regulations, it is important that an accurate environmental noise prediction method be used during the planning stage. This paper presents a comparison of predicted noise levels from four commonly applied prediction methods against measured noise levels from the operational wind farm conducted in accordance with the applicable guidelines in South Australia. The results indicate that the methods typically over-predict wind farm noise levels but that the degree of conservatism appears to depend on the topography between the wind turbines and the measurement location.

Comparison of compliance results obtained from the various wind farm standards used in Australia

Jonathan Cooper1, Tom Evans2 and Luis Najera2
1 Resonate Acoustics, 97 Carrington Street, Adelaide, SA 5000
2 AECOM, Level 28, 91 King William Street, Adelaide, SA 5000

Vol. 40, No. 1 pp 37 - 44 (2012)
ABSTRACT: There are a number of standards and guidelines which are used in Australia for the assessment of wind farm noise, most of which provide different methods for measuring compliance once the wind farm is operational. This paper examines the differences that result when assessing compliance against the various compliance measurement and analysis procedures. Compliance measurements from a thirteen receivers at distances of 300 metres to 3 kilometres from six wind farm sites are used in the analysis. Differences of between 1.9 and 4.3 dB(A) are observed between the highest and lowest assessment results obtained at individual receivers, although this range is reduced to 1.9 - 2.7 dB(A) when LAeq results that appeared to be influenced by extraneous noise are discarded. These results complement the findings of our other paper which compares predicted levels against the compliance measurement results, and together these papers can be used to compare predictions against wind turbine noise levels measured and analysed using the different methodologies.

Measurement and level of infrasound from wind farms and other sources

Chris Turnbull1, Jason Turner1 and Daniel Walsh2
1 Sonus Pty Ltd, 17 Ruthven Avenue, Adelaide, South Australia 5000
2 Pacific Hydro Level 11, 474 Flinders Street, Melbourne, Victoria 3000

Vol. 40, No. 1 pp 45 - 50 (2012)
ABSTRACT: Infrasound is generated by a range of natural and engineered sources. The measurement of infrasound at low levels requires a specific methodology, as it is readily affected by even light surface breezes on the microphone. Such a methodology, based on measurements below the ground surface in a test chamber, has been developed to measure infrasound at two Australian wind farms and also in the vicinity of a beach, a coastal cliff, the city of Adelaide and a power station. The measured levels have been compared between each source and against the infrasound audibility threshold of 85 dB(G). The measured level of infrasound within the wind farms is well below the audibility threshold and is similar to that of urban and coastal environments and near other engineered noise sources.

Analysis techniques for wind farm sound level measurements

Michael Smith and Stephen Chiles
URS, Christchurch, New Zealand. This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Vol. 40, No. 1 pp 51 - 56 (2012)
ABSTRACT: NZS 6808 and other similar wind farm assessment standards require sound level measurements at neighbouring houses with and without the wind farm operating. While outlining a procedure for assessment using regression curves, the standards allow significant discretion in how the data are analysed. Issues with this analysis are reviewed and suggestions are made as to how specific parts of the process could be standardised. These issues are illustrated with background sound datasets from actual wind farm proposals. In particular, this paper examines: the process for separation of data by time-of-day and wind direction; the effects of altering the wind speed range for analysis; use of bin analysis; and removal of outliers.

The steep and the tearful - a New Zealand perspective of wind turbine noise

Stuart Camp
Marshall Day Acoustics Ltd, Christchurch, New Zealand

Vol. 40, No. 1 pp 57 - 58 (2012)

Noise dose assessment of wind farm noise

Andy McKenzie
Hayes McKenzie Partnership, Salisbury, UK

Vol. 40, No. 1 pp 59 - 61 (2012)

Finding the character of wind turbine sound

Bob Thorne
Principal, Noise Measurement Services Pty Ltd, Brisbane QLD 4051

Vol. 40, No. 1 pp 62 - 63 (2012)

Low frequency, infrasound and amplitude modulation noise from wind farms - some recent findings

Colin Tickell
Senior Consultant – Environment and Acoustics, Hatch Associates, Neutral Bay, Australia

Vol. 40, No. 1 pp 64 - 66 (2012)
ABSTRACT: This article reviews some recent papers describing low-frequency, infrasound and amplitude-modulation noise from wind turbines, and whether low-frequency and infrasound from wind farms is a real, measurable issue. Some of the information was included in a literature review for the MOE Ontario. Some new information on low-frequency sound and amplitude- modulation at different angular locations from wind turbines presented at Inter-Noise 2011 in Osaka are also included in this review. One proposal for low frequency noise objectives is also discussed.

Wind turbine syndrome - an alternative view

Dick Bowdler
The Haven, Low Causeway, Culross, Fife, UK, This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Vol. 40, No. 1 pp 67 - 71 (2012)
ABSTRACT: There is a view in many countries that there is something “different” in wind turbine noise, usually considered to be infrasound, that makes people ill even at distances up to 10km. This paper presents the view that there is a simpler explanation and one which many acousticians know about from personal experience. Apart from the level and the character of turbine noise, non-acoustic factors contribute to the annoyance people feel. That annoyance brings stress which produces the symptoms described. The non-acoustic factors are largely attributable to the manner in which wind farms are developed, in particular, governments’ dismissal of a few people with a real problem as antisocial.

A review of the Draft NSW Planning Guidelines: Wind Farms

Justin Adcock, Christophe Delaire and Dan Griffin
Marshall Day Acoustics, Collingwood, VIC 3066

Vol. 40, No. 1 pp 72 - 78 (2012)
ABSTRACT: The recently published NSW Planning Guidelines - Wind Farms (the draft Guideline) presents a planning and assessment framework for a range of issues including recommendations for the assessment of noise impacts. These recommendations build upon existing assessment methods used throughout Australia, and helpfully include prescriptive guidance for a number of issues that are not well defined in existing guidance documents. Conversely, the draft Guideline introduces significant new requirements which may add a high level of complexity to the planning process. This technical note presents a discussion of some of the important features of the noise assessment recommendations proposed in the draft Guideline, including proposed noise criteria, measurement techniques, prediction methods and assessment of specific noise characteristics.

Development of the Draft NSW Planning Guidelines: Wind Farms

Jeff Parnell
Noise Specialist, NSW Department of Planning and Infrastructure

Vol. 40, No. 1 pp 79 - 83 (2012)

 

Newsflash

Spiders Tune In To Web's Music To Size Up Meals And MatesSpiders Tune In To Web's Music To Size Up Meals And Mates

Christopher Joyce: June 10, 2014

 

Noise – does it have a future?Noise – does it have a future?

ABC Radio National: February 4, 2014 by Antony Funnell

 

Din and dinner: Are our restaurants just too noisy?Din and dinner: Are our restaurants just too noisy?

The Age: Good Food: Food News article August 6, 2013 by Richard Cornish

 

Letter to the editor

Re Graham Lloyd’s article “World’s eyes will be on Waterloo as wind turbines go on trial

 

Say that again: tales of noisy noshSay that again: tales of noisy nosh

Episode from the Radio National Saturday 17 November 2012 1:06PM

Restaurant noise issues

 
43rd International Congress and Exposition on Noise Control Engineering
 

Restaurant Noise Survey

Restaurant Noise Survey "Café & Restaurant Acoustic Index (CRAI)"