Change search
Refine search result
1 - 23 of 23
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1. Andersson, B. L.
    et al.
    Bolin, Karl
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Cederholm, A.
    Karasalo, Ilkka
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL. FOI - Swedish Defence Research Agency, Sweden .
    Assessment of sound propagation modelling from a wind turbine site at sea2009In: 16th International Congress on Sound and Vibration 2009, ICSV 2009, 2009, p. 896-903Conference paper (Refereed)
    Abstract [en]

    We present results from numerical modelling of sound propagation from Utgrunden lighthouse in Kalmarsund to a receiver at Hammarby on the island Ö land east of Sweden in the Baltic. The propagation distances from source to shore and from shore to receiver are ca 9 km and 0.7 km, respectively. Our purpose is to assess prediction of atmospheric sound propagation by methods that use detailed knowledge of the local geometry and meteorology, by comparing model predictions of the transmission loss with experimental data. The experimental data, collected several times daily during a one-week campaign in June 2005, consist of (i) data on the transmission loss of narrow band signals from controlled sources with frequencies 80 Hz, 200 Hz and 400 Hz, (ii) atmospheric parameters as function of height from radio-soundings and balloon-tracking at the receiver location and (iii) atmospheric parameters from sensors mounted on a meteorological mast at the source location. Model-predicted soundfields were computed once per hour during the one-week period, with a windfield composed of a laminar field determined from data at the receiver, superimposed by a turbulent field determined by data from the meteorological mast. Comparisons of the experimentally observed transmission loss with predictions by the Green's Function Parabolic Equation (GFPE) method by Gilbert and Di are presented. A reasonably good fit of the model predicted transmission loss as function of time to experimental data at all frequencies is observed.

  • 2.
    Bolin, Karl
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Influence of turbulence and wind speed profiles on vegetation noiseManuscript (Other academic)
  • 3.
    Bolin, Karl
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Masking of wind turbine sound by ambient noise2006Licentiate thesis, comprehensive summary (Other scientific)
    Abstract [en]

    The main objective of this work was to gain an increasing understanding of the properties of vegetation noise and also to the relative ratios of different natural ambient noises to mask wind turbine sound.

    A discrete vegetation noise model was developed and compared to an earlier model showing improved estimations, especially at frequencies below 0.5 kHz. Field measurements of sound from deleafed trees are compared to a deleafed tree model with satisfactory agreement. A wind turbulence model (Sandia method) was coupled to the discrete model and thereby time series of fluctuating vegetation noise can be computed. Several measurements including higher wind speeds than reported in earlier literature were compared to predictions of fluctuating vegetation noise with good agreement.

    Psycho acoustic tests was performed by 36 subjects to determine the signal-to-noise (S/N) ratios when wind turbine noise is inaudible in three different natural ambient noises. The masking threshold varied between -6.5 dBA and -2.7 dBA for coniferous tree noise and sea wave noise respectively. Further tests revealed that at S/N ratios of +3dBA and above the wind turbine noise was considered as the dominant sound source.

  • 4.
    Bolin, Karl
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Prediction method for vegetation noiseManuscript (Other academic)
  • 5.
    Bolin, Karl
    KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW.
    Prediction Method for Wind-Induced Vegetation Noise2009In: Acta Acoustica united with Acustica, ISSN 1610-1928, E-ISSN 1861-9959, Vol. 95, no 4, p. 607-619Article in journal (Refereed)
    Abstract [en]

    This article examines the sound generated when the wind interacts with vegetation. A wind field model has been coupled to a new method for predicting sound from vegetation. This includes predictions from coniferous, deciduous and leafless trees. The proposed prediction method and an earlier model have been compared with measurements which show improved agreement, in particular in the region below 1 kHz. Comparisons between five measurement sites and predictions show satisfactory agreement for wind speeds up to 8.5 m/s. Fluctuations in the vegetation noise level due to wind turbulence can also be accurately estimated.

  • 6.
    Bolin, Karl
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Wind Turbine Noise and Natural Sounds: Masking, Propagation and Modeling2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Wind turbines are an environmentally friendly and sustainable power source. Unfortunately, the noise impact can cause deteriorated living conditions for nearby residents. The audibility of wind turbine sound is influenced by ambient sound. This thesis deals with some aspects of noise from wind turbines. Ambient sounds influence the audibility of wind turbine noise. Models for assessing two commonly occurring natural ambient sounds namely vegetation sound and sound from breaking waves are presented in paper A and B. A sound propagation algorithm has been compared to long range measurementsof sound propagation in paper C. Psycho-acoustic tests evaluating the threshold and partial loudness of wind turbine noise when mixed with natural ambient sounds have been performed. These are accounted for in paper D.

    The main scientific contributions are the following.Paper A: A semi-empiric prediction model for vegetation sound is proposed. This model uses up-to-date simulations of wind profiles and turbulent wind fields to estimate sound from vegetation. The fluctuations due to turbulence are satisfactory estimated by the model. Predictions of vegetation sound also show good agreement to measured spectra.

    Paper B: A set of measurements of air-borne sound from breaking waves are reported. From these measurements a prediction method of sound from breaking waves is proposed. Third octave spectra from breaking waves are shown to depend on breaker type. Satisfactory agreement between predictions and measurements has been achieved.

    Paper C: Long range sound propagation over a sea surface was investigated. Measurements of sound transmission were coordinated with local meteorological measurements. A sound propagation algorithm has been compared to the measured sound transmission. Satisfactory agreement between measurements and predictions were achieved when turbulence were taken into consideration in the computations.

    Paper D: The paper investigates the interaction between wind turbine noise and natural ambient noise. Two loudness models overestimate the masking from two psychoacoustic tests. The wind turbine noise is completely concealed when the ambient sound level (A-weighed) is around 10 dB higher than the wind turbine noise level. Wind turbine noise and ambient noise were presented simultaneously at the same A-weighed sound level. The subjects then perceived the loudness of the wind turbine noise as 5 dB lower than if heard alone.

    Keywords: Wind turbine noise, masking, ambient noise, long range sound propagation

  • 7.
    Bolin, Karl
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Almgren, Martin
    Ohlsson, Esbjörn
    Karasalo, Ilkka
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Long term estimations of low frequency noise levels over water from an off-shore wind farm2014In: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 135, no 3, p. 1106-1114Article in journal (Refereed)
    Abstract [en]

    This article focuses on computations of low frequency sound propagation from an off-shore wind farm. Two different methods for sound propagation calculations are combined with meteorological data for every 3 hours in the year 2010 to examine the varying noise levels at a reception point at 13 km distance. It is shown that sound propagation conditions play a vital role in the noise impact from the off-shore wind farm and ordinary assessment methods can become inaccurate at longer propagation distances over water. Therefore, this paper suggests that methodologies to calculate noise immission with realistic sound speed profiles need to be combined with meteorological data over extended time periods to evaluate the impact of low frequency noise from modern off-shore wind farms.

  • 8.
    Bolin, Karl
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Bluhm, Gosta
    Nilsson, Mats E.
    Listening Test Comparing A-Weighted and C-Weighted Sound Pressure Level as Indicator of Wind Turbine Noise Annoyance2014In: Acta Acoustica united with Acustica, ISSN 1610-1928, E-ISSN 1861-9959, Vol. 100, no 5, p. 842-847Article in journal (Refereed)
    Abstract [en]

    A listening test was conducted to investigate whether A-or C-weighed sound levels are most suitable as indicator of annoyance due to wind turbine noise. The tests consisted of fifteen different wind turbine noises presented at eight sound levels together with pink noise signals as reference sounds. A total number of 31 persons performed the listening test divided into two subgroups. The first group comprising of 20 students conducted the test in a semi anechoic chamber, and the second group of 11 residents annoyed by wind turbine noise in their homes, conducted the test in their own homes. Results from both subgroups showed that A-weighed sound levels were a more accurate description of wind turbine noise annoyance than C-weighed sound levels. The residents found the same wind turbine noises more annoying than the students, indicating a higher sensitivity to wind turbine noise among persons a priori annoyed by this noise and exposed to this source in their residential settings.

  • 9.
    Bolin, Karl
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Bluhm, Gösta
    Eriksson, Gabriella
    Nilsson, Mats E.
    Infrasound and low frequency noise from wind turbines: exposure and health effects2011In: Environmental Research Letters, ISSN 1748-9326, E-ISSN 1748-9326, Vol. 6, no 3, p. 035103-Article in journal (Refereed)
    Abstract [en]

    Wind turbines emit low frequency noise (LFN) and large turbines generally generate more LFN than small turbines. The dominant source of LFN is the interaction between incoming turbulence and the blades. Measurements suggest that indoor levels of LFN in dwellings typically are within recommended guideline values, provided that the outdoor level does not exceed corresponding guidelines for facade exposure. Three cross-sectional questionnaire studies show that annoyance from wind turbine noise is related to the immission level, but several explanations other than low frequency noise are probable. A statistically significant association between noise levels and self-reported sleep disturbance was found in two of the three studies. It has been suggested that LFN from wind turbines causes other, and more serious, health problems, but empirical support for these claims is lacking.

  • 10.
    Bolin, Karl
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Boue, Mathieu
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Karasalo, Ilkka
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Long range sound propagation over a sea surface2009In: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 126, no 5, p. 2191-2197Article in journal (Refereed)
    Abstract [en]

    This paper describes methodology and results from a model-based analysis of data on sound transmission from controlled sound sources at sea to a 10-km distant shore. The data consist of registrations of sound transmission loss together with concurrently collected atmospheric data at the source and receiver locations. The purpose of the analysis is to assess the accuracy of methods for transmission loss prediction in which detailed data on the local geography and atmospheric conditions are used for computation of the sound field. The results indicate that such sound propagation predictions are accurate and reproduce observed variations in the sound level as function of time in a realistic way. The results further illustrate that the atmospheric model must include a description of turbulence effects to ensure predicted noise levels to remain realistically high during periods of sound shadow. (C) 2009 Acoustical Society of America. [DOI: 10.1121/1.3238236]

  • 11.
    Bolin, Karl
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, MWL Flow acoustics.
    Kedhammar, Anders
    Nilsson, Mats E.
    The Influence of Background Sounds on Loudness and Annoyance of Wind Turbine Noise2012In: Acta Acoustica united with Acustica, ISSN 1610-1928, E-ISSN 1861-9959, Vol. 98, no 5, p. 741-748Article in journal (Refereed)
    Abstract [en]

    Natural sounds may create pleasant soundscapes that mask wind turbine noise. To explore this, a listening test was performed to investigate the influence of background sounds on perceived loudness and annoyance of wind turbine noise. A magnitude estimation method was used to measure perceived loudness and annoyance of wind turbine noise heard together with and without natural ambient sounds. Results indicate that decreased loudness and annoyance occurs if the level of the background sound exceeds the level of the wind turbine noise. The loudness experiment revealed that ambient sounds influenced the perception of wind turbine noise to a higher degree than predicted from a model of energetic masking. Annoyance ratings were less altered by background sound than perceived loudness. The results of the present listening study indicates that masking of wind turbine noise by positive natural sounds may be used as a complement to conventional noise control measures to improve the sound environment in areas exposed to wind turbine noise.

  • 12.
    Bolin, Karl
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Khan, S.
    Determining the potentiality of masking wind turbine noise using natural ambient noise2006In: Acta Acoustica united with Acustica, ISSN 1610-1928, E-ISSN 1861-9959Article in journal (Other academic)
  • 13.
    Bolin, Karl
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Nilsson, Mats E
    Karolinska Institutet, Inst. för Miljömedicin.
    Khan, Shafiquzzaman
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    The Potential of Natural Sounds to Mask Wind Turbine Noise2010In: Acta Acoustica united with Acustica, ISSN 1610-1928, E-ISSN 1861-9959, Vol. 96, no 1, p. 131-137Article in journal (Refereed)
    Abstract [en]

    Wind turbine (WT) noise may cause annoyance, especially in relatively quiet areas with low ambient levels. As a compliment to conventional noise control at the source, addition of wanted sounds may reduce the loudness of WT noise by auditory masking. In order to test this, two masking experiments were conducted with two WT noises as target sounds and three natural sounds as maskers (wind in coniferous or deciduous trees and sea waves). In the first experiment, 30 listeners determined the detection thresholds of WT noise in the presence of the natural sounds using a threshold tracking method. In the second experiment, the same group of listeners matched the loudness of partially masked WT noise with the loudness of unmasked WT noise. The results showed that detection thresholds for WT-noise in the presence of natural sounds from trees and sea waves were around -8 to -12 dB S/N-ratio. Furthermore, a reduction of perceived loudness of WT-noise was found for S/N-ratios up to 2 dB. These results were compared with predictions from two models of partial masking (steady and time variant). In general, empirically determined detection thresholds and partial loudness matches were higher than predictions from the two models.

  • 14.
    Bolin, Karl
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Åbom, Mats
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Air-borne sound generated by sea waves2010In: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 127, no 5, p. 2771-2779Article in journal (Refereed)
    Abstract [en]

    This paper describes a semi-empiric model and measurements of air-borne sound generated by breaking sea waves. Measurements have been performed at the Baltic Sea. Shores with different slopes and sediment types have been investigated. Results showed that the sound pressure level increased from 60 dB at 0.4 m wave height to 78 dB at 2.0 m wave height. The 1/3 octave spectrum was dependent on the surf type. A scaling model based on the dissipated wave power and a surf similarity parameter is proposed and compared to measurements. The predictions show satisfactory agreement to the measurements. (C) 2010 Acoustical Society of America. [DOI: 10.1121/1.3327815]

  • 15.
    Dickson, Crispin
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Bolin, Karl
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Continuous judgment by category-ratio scaling of aircraft noise2014In: Applied Acoustics, ISSN 0003-682x, Vol. 84, p. 3-8Article in journal (Refereed)
    Abstract [en]

    A continuous judgment by category-ratio (CJCR) scaling method was used to evaluate the instantaneous annoyance of original and modified aircraft sounds. The result from the proposed method resulted in a temporal stream of annoyance levels for the whole flyover sequence that could be further analyzed. The test subjects were continuously rating their instantaneous annoyance on a Borg CR 100 scale (R) during the playback of 10 flyover sequences. Using a category-ratio (CR) scale instead of a category (C) scale, mathematical operations such as calculations of average were enabled but gave also advantages in terms of higher resolution in the responses. The results showed differences in perception in the time segment where the sound had been modified. The temporal stream of annoyance was also converted into overall judgments of the sounds, these estimations showed consistency with previous results obtained using the semantic differential and paired comparison method.

  • 16. Griefahn, B.
    et al.
    Bolin, Karl
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Flindell, I.
    Lambert, J.
    Lavandier, C.
    Marki, F.
    Müller, U.
    Moderators that influence annoyance of residents near 6 European airports2013In: 42nd International Congress and Exposition on Noise Control Engineering 2013, INTER-NOISE 2013: Noise Control for Quality of Life, OAL-Osterreichischer Arbeitsring fur Larmbekampfung , 2013, p. 1072-1080Conference paper (Refereed)
    Abstract [en]

    The aim of the present study was to identify possible moderator variables that influence annoyance due to aircraft noise. The data analysed here were ascertained by extended questionnaires in three studies within the COSMA-Project that was funded by the European Union. There were a Field Study and a Telephone Interview, each performed with residents living in the vicinity of the airports Cologne-Bonn, London Heathrow or Stockholm- Arlanda and a Laboratory Study performed with residents living near the airports Budapest, Lyon or Paris. In each of the three studies (and the overall 9 subgroups) the participants completed extended questionnaires on long- Term annoyance. In the field study sleep behaviour and acute annoyance that was rated each hour were additionally ascertained over a period of 4 days. Using a logistic regression model analysis odds ratios were determined for possible moderators. Based on the results a model was created that shows the most important negative and positive influences.

  • 17. Nilsson, M. E.
    et al.
    Alvarsson, J.
    Rådsten-Ekman, M.
    Bolin, Karl
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Loudness of fountain and road traffic sounds in a city park2009In: 16th International Congress on Sound and Vibration 2009, ICSV 2009, 2009, p. 1270-1276Conference paper (Refereed)
    Abstract [en]

    Auditory masking of unwanted sounds by wanted sounds has been suggested as an approach to soundscape improvement. Anecdotal evidence exists on successful applications, for instance use of fountain sounds for masking road traffic noise in urban parks. However, basic research on auditory masking of environmental sounds is lacking. Therefore, we conducted two listening experiments on auditory masking, using binaural recordings from a city park in Stockholm exposed to traffic noise from a main road and sound from a large fountain located in the centre of the park. In Experiment 1, 12 listeners assessed the loudness of road traffic noise and fountain sounds from recordings at various distances from road, with or without the fountain turned on. In Experiment 2, the same listeners assessed loudness of manipulated sound levels of singular or combined road traffic or fountain sounds. The results of Experiment 1 showed that the fountain sound reduced the loudness of road traffic noise close to the fountain, and that the fountain sound was equally loud or louder than the road traffic noise in a region 20-30 m around the fountain. This suggests that fountain sounds may add to the quality of city park soundscape by reducing the loudness of the (presumably unwanted) traffic noise. On the other hand, results from both experiments showed that road traffic noise was harder to mask than fountain sound. Furthermore, Experiment 2 showed that partial loudness of both sources was considerably less than expected from a model of energetic masking. This suggests that informational masking due to target-masker similarity may reduce the overall masking effect of environmental sounds.

  • 18. Nilsson, M. E.
    et al.
    Bolin, Karl
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Bluhm, G.
    Replik om vindkraft: Vindkraftsbuller är inte ett infraljudsproblem2013In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 110, no 42, p. 1877-Article in journal (Refereed)
  • 19. Nilsson, Mats E.
    et al.
    Alvarsson, Jesper
    Radsten-Ekman, Maria
    Bolin, Karl
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Auditory masking of wanted and unwanted sounds in a city park2010In: Noise Control Engineering Journal, ISSN 0736-2501, E-ISSN 2168-8710, Vol. 58, no 5, p. 524-531Article in journal (Refereed)
    Abstract [en]

    Auditory masking of unwanted sounds by wanted sounds has been suggested as a tool for outdoor acoustic design. Anecdotal evidence exists for successful applications, for instance the use of fountain sounds for masking road traffic noise in urban parks. However, basic research on auditory masking of environmental sounds is lacking. Therefore, we conducted two listening experiments, using binaural recordings from a city park in Stockholm exposed to traffic noise from a main road and sound from a large fountain located in the center of the park. In the first experiment, 17 listeners assessed the loudness of the road traffic noise and fountain sounds from recordings at various distances from the road, with or without the fountain turned on. In the second experiment, 16 listeners assessed the loudness of systematic combinations of a singular fountain sound and a singular road traffic noise. The results of the first experiment showed that the fountain sound reduced the loudness of road traffic noise close to the fountain, and that the fountain sound was equally loud or louder than the road traffic noise in a region 20-30 m around the fountain. This suggests that the fountain added to the quality of the city park soundscape by reducing the loudness of the (presumably unwanted) traffic noise. On the other hand, results from the second experiment showed that road traffic noise was harder to mask than fountain sound, and that the partial loudness of both sources was considerably less than expected from a model of energetic masking. This indicates that auditory processes, possibly related to target-masker confusion, may reduce the overall masking effect of environmental sounds.

  • 20.
    Rasam, Amin
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Botha, Jason D. M.
    Trinity College Dublin, Department of Mechanical and Manufacturing Engineering, Ireland.
    Karl, Bolin
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    O'Reilly, Ciarán J.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center for ECO2 Vehicle design.
    Efraimsson, Gunilla
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center for ECO2 Vehicle design.
    Rice, Henry J.
    Trinity College Dublin, Department of Mechanical and Manufacturing Engineering, Ireland.
    Aerodynamic noise prediction for a wind turbine using numerical flow simulations and semi-empirical modelling approaches2016In: 22nd AIAA/CEAS Aeroacoustics Conference, American Institute of Aeronautics and Astronautics, 2016Conference paper (Other academic)
    Abstract [en]

    In this paper, aerodynamic and aero-acoustic simulations are performed for a small horizontal axis wind turbine, suitable for the integration of wind energy in urban and peri-urban areas. Detached-eddy simulation (DES) of compressible flow is performed to compute the flow field over the wind turbine. The far-field noise is computed using the Ffowcs - Williams and Hawkings acoustic analogy. Furthermore, the blade element momentum theory is used with a semi-empirical acoustic modeling approach to predict the wind turbine noise. The acoustic modeling approach is based on a semi-empirical formulation for airfoil self noise and an analytic formulation for inflow noise.

  • 21.
    Rasam, Amin
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Karl, Bolin
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    O'Reilly, Ciarán J.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center for ECO2 Vehicle design.
    Detached-eddy simulation of a horizontal-axis wind turbine2016In: 6th Symposium on Hybrid RANS-LES Methods, 2016Conference paper (Other academic)
    Abstract [en]

    Aerodynamic simulations of a small horizontal-axis wind turbine, suit- able for integration of wind energy in urban and peri-urban areas, are performed. Im- proved delayed detached-eddy simulation is used in the computations. Simulations are carried out for three rotation rates and inlet conditions. Aerodynamic charac- teristics of the wind turbine such as forces, power production, pressure distribution as well as flow topology are presented. The effect of different rotation rates on the turbine aerodynamics is discussed. 

  • 22.
    Rasam, Amin
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Pouransari, Zeinab
    KTH, School of Engineering Sciences (SCI), Solid Mechanics (Dept.).
    Bolin, Karl
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    O'Reilly, Ciarán J.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Detached-eddy simulation of a horizontal axis wind turbine2018In: Progress in Hybrid RANS-LES Modelling: Papers Contributed to the 6th Symposium on Hybrid RANS-LES Methods, 26-28 September 2016, Strasbourg, France, Springer, 2018, p. 357-367Chapter in book (Refereed)
    Abstract [en]

    Aerodynamic simulations of a small horizontal-axis wind turbine, suitable for integration of wind energy in urban and peri-urban areas, are performed using the improved delayed detached-eddy simulation method. Simulations are carried out for three rotation rates and inlet conditions. Aerodynamic characteristics of the wind turbine such as forces, power production, pressure distribution as well as flow topologies are presented. The effect of different rotation rates as well as the effect of free stream turbulence on the turbine aerodynamics are discussed.

  • 23.
    Åbom, Mats
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL. KTH-Centre for Sustainable Aviation.
    Bolin, Karl
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL. KTH-Centre for Sustainable Aviation.
    Ulfvengren, Pernilla
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.), Industrial Management. KTH-Centre for Sustainable Aviation.
    Air traffic management and noise2018In: INTER-NOISE 2018 - 47th International Congress and Exposition on Noise Control Engineering: Impact of Noise Control Engineering, Institute of Noise Control Engineering , 2018Conference paper (Refereed)
    Abstract [en]

    With the steady increase of air traffic the need for developing sustainable aviation increases as well. To meet this need, the Swedish Transport Administration and KTH Royal Institute of Technology have established a Centre for Sustainable Aviation. In a global perspective, aviation research focuses on meeting future capacity needs for increased travel and at the same time achieve sustainability with reduced environmental impact and sustained or increased safety. This paper describes four on-going projects, as examples of the variety of research that may contribute to a sustainable society in both shorter and longer terms as well as both in a local and in an international perspective. Initially the centre will apply and direct existing knowledge towards noise abatement initiatives in aviation. I the long-term perspective the research will contribute to knowledge on a broader spectrum of sustainability aspects of aviation.

1 - 23 of 23
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf