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Publications (10 of 114) Show all publications
Ågren, A. & Ljunggren, F. (2016). In situ measured flanking transmission in light weight timber houses with elastic flanking isolators: Part II (ed.). In: (Ed.), von Estorff O., Kropp W., Schulte-Fortkamp B (Ed.), InterNoise 2016: 45th International Congress and Exposition on Noise Control Engineering: Towards a Quieter Future. Paper presented at 45th International Congress and Exposition on Noise Control Engineering,Hamburg, 21-24 August 2016 (pp. 3772-3781). German Acoustical Society
Open this publication in new window or tab >>In situ measured flanking transmission in light weight timber houses with elastic flanking isolators: Part II
2016 (English)In: InterNoise 2016: 45th International Congress and Exposition on Noise Control Engineering: Towards a Quieter Future / [ed] von Estorff O., Kropp W., Schulte-Fortkamp B, German Acoustical Society , 2016, p. 3772-3781Conference paper, Published paper (Refereed)
Abstract [en]

There is a strong trend to industrially produce multi-storey light weight timber based houses. The concept allows the buildings to be manufactured to a more or less prefabricated extent. Most common types are volume/room modules or flat wall and floor modules. When assembling the modules at the building site, elastomer isolators are used in several constructions to reduce flanking transmission. The sound insulation demands in the Nordic countries are relatively high and therefore the flanking transmission must be well controlled, where elastomer isolators are an established alternative. Decoupled shielding wall elements is another. There are though no working studies or mathematical models of the performance of these isolators. They are treated as simple mass-springs systems that operate vertically, i.e. one degree of freedom. In this paper there are analyses of an expanded set of experimental data of the structure borne sound isolating performance of elastomer isolators, which are separating an excited floor from receiving walls. This part II study now includes all in all 9 buildings. The isolation performance dependence on structure type is analyzed. An empirically based regression model of the vibration level difference is derived. The model is based on measurements of 8 elastomer field installations, which are compared to an installation without elastomers. A goal is that the data can be used for input in future SEN prediction models for modeling of the flanking transmission part of sound insulation

Place, publisher, year, edition, pages
German Acoustical Society, 2016
National Category
Fluid Mechanics and Acoustics
Research subject
Engineering Acoustics
Identifiers
urn:nbn:se:ltu:diva-60710 (URN)2-s2.0-84994632122 (Scopus ID)
Conference
45th International Congress and Exposition on Noise Control Engineering,Hamburg, 21-24 August 2016
Available from: 2016-11-28 Created: 2016-11-28 Last updated: 2017-11-24Bibliographically approved
Normark, C. J., Tretten, P., Grane, C., Ågren, A., Lundkvist, A. & Nykänen, A. (2014). Project: Human Factors LAB. Paper presented at .
Open this publication in new window or tab >>Project: Human Factors LAB
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2014 (English)Other (Other (popular science, discussion, etc.))
National Category
Other Engineering and Technologies not elsewhere specified Other Civil Engineering Production Engineering, Human Work Science and Ergonomics Fluid Mechanics and Acoustics
Research subject
Industrial Design; Operation and Maintenance; Engineering Psychology; Engineering Acoustics
Identifiers
urn:nbn:se:ltu:diva-35982 (URN)08449ca9-13da-4311-aa45-c1bb5e48d6e6 (Local ID)08449ca9-13da-4311-aa45-c1bb5e48d6e6 (Archive number)08449ca9-13da-4311-aa45-c1bb5e48d6e6 (OAI)
Note

Publikationer: Exploring user needs in automobiles; Personalizable in-vehicle systems, technology acceptance and product attachment; Personalizable Vehicle Interfaces for Better User Experience; What drivers really want: Investigating dimensions in automobile user needs; Assessment of automotive visual display guidelines and principles: a literature review; Design and evaluation of a personalizable interface in a vehicle context; The development of an aircraft maintenance technician headset; Status: Pågående; Period: 02/01/2013 → …

Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2017-11-25Bibliographically approved
Lennström, D., Johnsson, R., Ågren, A. & Nykänen, A. (2014). The influence of the acoustic transfer functions on the estimated interior noise from an electric rear axle drive (ed.). Paper presented at . SAE International Journal of Passenger Cars - Mechanical Systems, 7(1), 413-422
Open this publication in new window or tab >>The influence of the acoustic transfer functions on the estimated interior noise from an electric rear axle drive
2014 (English)In: SAE International Journal of Passenger Cars - Mechanical Systems, ISSN 1946-3995, E-ISSN 1946-4002, Vol. 7, no 1, p. 413-422Article in journal (Refereed) Published
Abstract [en]

In the vehicle development process, targets are defined to fulfill customers' expectations on acoustic comfort. The interior complete vehicle acoustic targets can be cascaded down to system and component targets, e.g. insulation properties and source strengths. The acoustic transfer functions (ATFs) from components radiating airborne noise play a central role for the interior sound pressure levels. For hybrid vehicles fitted with an electric traction motor, the contribution of high frequency tonal components radiated from the motor housing needs to be controlled. The interior sound pressure due to an airborne motor order can be estimated by surface velocities and ATFs. This study addresses the ATFs measured from a large number of positions located around an electric rear axle drive (ERAD) and their influence on estimated interior noise. First, the magnitude variation between the individual ATFs and how it clearly can be visualized was presented. Displaying all ATFs in a color map revealed the magnitude at each geometrical location of the respective microphone. Secondly, the influence of the ATF's spatial resolution on estimated interior sound pressure was investigated. This was done for theoretical models of the stator shell source shape and also for measured surface velocities. By reducing the spatial resolution from 0.05 to 0.10 m between each microphone, the difference in noise contribution is typically within three decibels with a 12th octave smoothing filter applied to the narrow-band data. The findings from this work provide insight in the risks of compromising with the number of ATF's needed for contribution analysis.

National Category
Fluid Mechanics and Acoustics
Research subject
Engineering Acoustics
Identifiers
urn:nbn:se:ltu:diva-15567 (URN)10.4271/2014-01-9124 (DOI)2-s2.0-84903448650 (Scopus ID)f190d2d1-d64f-4785-a9ba-0846789779b3 (Local ID)f190d2d1-d64f-4785-a9ba-0846789779b3 (Archive number)f190d2d1-d64f-4785-a9ba-0846789779b3 (OAI)
Projects
CASTT - Centre for Automotive Systems Technologies and Testing
Note
Godkänd; 2014; 20140805 (johsod)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Lennström, D., Johnsson, R., Nykänen, A. & Ågren, A. (2013). Determination of radiated sound power from an electric rear axle drive in-situ and its contribution to interior noise (ed.). Paper presented at . SAE technical paper series, 6(3), 1554-1563
Open this publication in new window or tab >>Determination of radiated sound power from an electric rear axle drive in-situ and its contribution to interior noise
2013 (English)In: SAE technical paper series, ISSN 0148-7191, Vol. 6, no 3, p. 1554-1563Article in journal (Refereed) Published
Abstract [en]

System and component target setting for noise and vibration are important activities within automotive product development. New challenges arise when electric motors are introduced into cars traditionally powered by combustion engines. The emitted noise from an electric traction motor for hybrid electric vehicles is characterized by high frequency tonal components from the dominating magnetic harmonics which can be perceived as annoying. Sound power is frequently used for quantifying the airborne noise from rotating electrical machines. This paper describes the process of determining the radiated sound power from an automobile electric rear axle drive in-situ and its contribution to interior cabin noise for a prominent rotor order. The sound power was calculated by combining the average stator surface vibration velocity together with an estimate of the radiation efficiency. To model the radiation efficiency, the vibration shape of the cylindrically shaped stator shell was determined by means of operational deflection shapes. The acoustic transfer functions between the source and receiver positions close to a passenger's ear, were defined as the ratio of sound pressure and sound power. By combining the acoustic transfer functions with the calculated operational sound power, the airborne interior noise can be predicted. The calculated interior noise levels were found to be in accordance, within approximately 3 dB, with the measured airborne noise from the stator shell. This indicated that the method is valid and could be helpful for calculating allowed radiated power from interior noise targets and acoustic transfer functions.

National Category
Fluid Mechanics and Acoustics
Research subject
Engineering Acoustics
Identifiers
urn:nbn:se:ltu:diva-5996 (URN)10.4271/2013-01-9120 (DOI)2-s2.0-84924351999 (Scopus ID)431bf4a7-f264-4fcc-8e42-f7bcfe390e7a (Local ID)431bf4a7-f264-4fcc-8e42-f7bcfe390e7a (Archive number)431bf4a7-f264-4fcc-8e42-f7bcfe390e7a (OAI)
Projects
CASTT - Centre for Automotive Systems Technologies and Testing
Note
Validerad; 2013; 20131129 (rojn)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Ljunggren, F. & Ågren, A. (2013). Elastic layers to reduce sound transmission in lightweight buildings (ed.). Paper presented at . Building Acoustics, 20(1), 25-42
Open this publication in new window or tab >>Elastic layers to reduce sound transmission in lightweight buildings
2013 (English)In: Building Acoustics, ISSN 1351-010X, Vol. 20, no 1, p. 25-42Article in journal (Refereed) Published
Abstract [en]

To obtain satisfactory sound insulation is a challenging task when designing lightweight buildings. Poor performance at low frequencies as well as severe flanking transmission has traditionally often been more pronounced compared to heavier constructions. In the present casestudy based paper, various aspects of using elastic layers to improve sound insulation in lightweight buildings are considered.The effect on impact and airborne sound insulation by using two different kinds of vibration insulators between floor plans was examined together with the effect of using glues of various degree of elasticity in the construction. In situ measurements were performed inside a four-storey wooden frame based residential building and statistically significant variations in sound insulation were found.The efficiency of the two vibration insulators was further evaluated by vibration reduction measurements over the junctions. The difference in vibration reduction was found to be nearly constant in the frequency range 50-1000 Hz while the improvement of impact sound insulation increased by frequency.Along term test of elastic glues was also conducted, during three years, for stability over time. The best glues preserved a significantly higher damping ratio over time compared to the main part of the glues.

National Category
Fluid Mechanics and Acoustics
Research subject
Engineering Acoustics
Identifiers
urn:nbn:se:ltu:diva-3480 (URN)10.1260/1351-010X.20.1.25 (DOI)2-s2.0-84879946891 (Scopus ID)14f36052-6bd7-41c1-90cd-a23206fa5288 (Local ID)14f36052-6bd7-41c1-90cd-a23206fa5288 (Archive number)14f36052-6bd7-41c1-90cd-a23206fa5288 (OAI)
Note
Validerad; 2013; 20130813 (frel)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Ågren, A. & Ljunggren, F. (2013). In situ measured flanking transmission in light weight timber houses with elastic flanking isolators (ed.). In: (Ed.), (Ed.), InterNoise 2013: Noise control for quality of life. Paper presented at International Congress and Exposition on Noise Control Engineering : 15/09/2013 - 18/09/2013 (pp. 1899-1908). INnsbruck, 3, Article ID 1019.
Open this publication in new window or tab >>In situ measured flanking transmission in light weight timber houses with elastic flanking isolators
2013 (English)In: InterNoise 2013: Noise control for quality of life, INnsbruck, 2013, Vol. 3, p. 1899-1908, article id 1019Conference paper, Published paper (Refereed)
Abstract [en]

There is a strong trend to industrially produce multi-storey light weight timber based houses. This concept allows the buildings to be manufactured to a more or less prefabricated extent. Most common types are volume/room modules or flat wall and floor modules. When assembling the modules at the building site, elastomer isolators are used in several constructions to reduce flanking transmission. The sound insulation demands in the Nordic countries are relatively high and therefore the flanking transmission must be well controlled, where elastomer isolators are an alternative. Decoupled radiation isolated walls is another. There are though no working studies or mathematical models of the performance of these isolators. They are only treated as simple mass-springs systems that operate vertically, i.e. one degree of freedom. In this paper there is an analysis of experimentally data of the structure borne sound isolating performance of elastomer isolators that are separating an excited floor from receiving walls. The performance dependence of structure type is also presented. An empirically based regression model of the vibration level difference is derived. The model is based on measurements of six elastomer field installations, which are compared to five comparable installations without elastomers. A goal is that the model can be used for input in future SEN prediction models for modeling of sound insulation.

Place, publisher, year, edition, pages
INnsbruck: , 2013
Keywords
Civil engineering and architecture - Building engineering, Natural sciences - Physics, Byggnadsakustik, akustik, Samhällsbyggnadsteknik och arkitektur - Byggnadsteknik, Naturvetenskap - Fysik
National Category
Fluid Mechanics and Acoustics
Research subject
Engineering Acoustics
Identifiers
urn:nbn:se:ltu:diva-38424 (URN)cd314d3c-5717-4945-a7aa-33f93b8fcf28 (Local ID)9781632662675 (ISBN)cd314d3c-5717-4945-a7aa-33f93b8fcf28 (Archive number)cd314d3c-5717-4945-a7aa-33f93b8fcf28 (OAI)
Conference
International Congress and Exposition on Noise Control Engineering : 15/09/2013 - 18/09/2013
Note
Godkänd; 2013; 20131106 (anag)Available from: 2016-10-03 Created: 2016-10-03 Last updated: 2017-11-25Bibliographically approved
Ågren, A., Ljunggren, F., Jarnerö, K. & Bolmsvik, Å. (2012). Flanking transmission in light weight timber houses with elastic flanking isolators (ed.). In: (Ed.), (Ed.), InterNoise 2012: . Paper presented at Inter Noise 2012 : 19/08/2012 - 22/08/2012 (pp. 2289-2300). , 3
Open this publication in new window or tab >>Flanking transmission in light weight timber houses with elastic flanking isolators
2012 (English)In: InterNoise 2012, 2012, Vol. 3, p. 2289-2300Conference paper, Published paper (Other academic)
Abstract [en]

There is a strong trend to industrially produce multi-storey light weight timber based houses. This concept allows the buildings to be manufactured to a more or less prefabricated extent. Most common types are volume/room modules or flat wall and floor modules. When assembling the modules at the building site, elastomer isolators are used in several constructions to reduce flanking transmission. The sound insulation demands in the Nordic countries are relatively high and therefore the flanking transmission must be well controlled, elastomer isolators is one choice. Decoupled radiation isolated walls is another. There are though no working studies or mathematical models of the performance of these isolators. They are only treated as simple mass-springs systems that operate vertically. In this paper there is a first approach of an analysis of the structure borne sound isolating performance of elastomer isolators that are separating floors and walls. The performance dependence of structure type is also presented. An empirically based regression model of the insertion loss is derived. The model will be based on measurements of more than ten field installations. In this paper the first three are presented. A goal is that the model can be used for input in future SEN prediction models for modeling of sound insulation.

National Category
Fluid Mechanics and Acoustics
Research subject
Engineering Acoustics
Identifiers
urn:nbn:se:ltu:diva-37257 (URN)b3b3d47e-e1a2-416b-ad2b-1e342fa82f4d (Local ID)9781627485609 (ISBN)b3b3d47e-e1a2-416b-ad2b-1e342fa82f4d (Archive number)b3b3d47e-e1a2-416b-ad2b-1e342fa82f4d (OAI)
Conference
Inter Noise 2012 : 19/08/2012 - 22/08/2012
Note
Godkänd; 2012; 20120924 (anag)Available from: 2016-10-03 Created: 2016-10-03 Last updated: 2017-11-25Bibliographically approved
Ljunggren, F. & Ågren, A. (2012). How to match building acoustic measurements with subjective judgments (ed.). In: (Ed.), (Ed.), Inter-Noise 2012: . Paper presented at Inter Noise 2012 : 19/08/2012 - 22/08/2012 (pp. 8922-8996). , 11
Open this publication in new window or tab >>How to match building acoustic measurements with subjective judgments
2012 (English)In: Inter-Noise 2012, 2012, Vol. 11, p. 8922-8996Conference paper, Published paper (Other academic)
Abstract [en]

The Swedish research program AkuLite deals with various aspects regarding sound and vibration within lightweight buildings. As the popularity of lightweight block of flats increases it has been noticed that standardised (ISO) measurements, like airborne and impact sound insulation, tend to show different correlation with subjective experiences compared with concrete buildings. It is therefore of importance to either develop existing evaluation methods or to find new measurement parameters for better correspondence. In the project, series of sound and vibration measurements are carried out in various types of buildings. The measurements include extended frequency range and various sources as well as increased number of extracted parameters compared to existing standards. In parallel, questionnaires are distributed to the tenants, in the same buildings, where they give answer to questions regarding the experienced sound annoyance in their flat. Statistical analysis of the correlation between the objective measurement parameters and the subjective opinions from the tenants will be carried out.

National Category
Fluid Mechanics and Acoustics
Research subject
Engineering Acoustics
Identifiers
urn:nbn:se:ltu:diva-27591 (URN)115dbe1d-0d9e-4d9b-ba08-5c1827e45638 (Local ID)9781627485609 (ISBN)115dbe1d-0d9e-4d9b-ba08-5c1827e45638 (Archive number)115dbe1d-0d9e-4d9b-ba08-5c1827e45638 (OAI)
Conference
Inter Noise 2012 : 19/08/2012 - 22/08/2012
Note
Godkänd; 2012; 20120924 (anag)Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2017-11-25Bibliographically approved
Öqvist, R., Ljunggren, F. & Ågren, A. (2012). On the uncertainty of building acoustic measurements: Case study of a cross-laminated timber construction (ed.). Paper presented at . Applied Acoustics, 73(9), 904-912
Open this publication in new window or tab >>On the uncertainty of building acoustic measurements: Case study of a cross-laminated timber construction
2012 (English)In: Applied Acoustics, ISSN 0003-682X, E-ISSN 1872-910X, Vol. 73, no 9, p. 904-912Article in journal (Refereed) Published
Abstract [en]

If variations and uncertainty in building acoustic measurements can be controlled, construction costs can potentially be reduced since the building will not have to be acoustically over-designed. Field measurements of impact and airborne sound insulation were carried out for an industrially prefabricated cross-laminated timber (CLT) system of plate elements. The results from 18 rooms, forming three groups with respect to size, were compared to a similar study dealing with a prefabricated Volume Based Building (VBB) system. Large variations were found at frequencies below 100 Hz which is crucial for the low frequency adaptation terms connected to the weighted sound insulation indices. The measurement uncertainty was investigated by analysing the repeatability, measurement direction and the time dependence of the sound source. The variations due to the measurement procedure were found to be small compared to the total variations. It was also indicated that the variations in sound insulation are smaller with a prefabricated system compared to on-site production, since less work is required at the building site

National Category
Fluid Mechanics and Acoustics
Research subject
Engineering Acoustics
Identifiers
urn:nbn:se:ltu:diva-14769 (URN)10.1016/j.apacoust.2012.03.012 (DOI)000305673300007 ()2-s2.0-84861639993 (Scopus ID)e30fdd61-692b-4f18-9db8-9dcaba2ca212 (Local ID)e30fdd61-692b-4f18-9db8-9dcaba2ca212 (Archive number)e30fdd61-692b-4f18-9db8-9dcaba2ca212 (OAI)
Note
Validerad; 2012; 20120418 (andbra)Available from: 2016-09-29 Created: 2016-09-29 Last updated: 2018-07-10Bibliographically approved
Grane, C., Normark, C. J., Lundkvist, A., Alm, H., Ågren, A., Broström, R. & Davidsson, S. (2012). Project: EFESOS - Environmental Friendly efficient Enjoyable and Safety Optimized Systems. Paper presented at .
Open this publication in new window or tab >>Project: EFESOS - Environmental Friendly efficient Enjoyable and Safety Optimized Systems
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2012 (Swedish)Other (Other (popular science, discussion, etc.))
Abstract [sv]

EFESOS is a Swedish Vehicle HMI (Human Machine Interaction) FFI research project. The overall ambition is to make driving of future cars more environmental friendly, enjoyable and safer by means of optimized systems. The project is managed by Volvo Car Corporation (VCC) and it is a collaboration between VCC and seven other research partners including Luleå University of Technology.

National Category
Production Engineering, Human Work Science and Ergonomics Other Engineering and Technologies not elsewhere specified Fluid Mechanics and Acoustics
Research subject
Engineering Psychology; Industrial Design; Engineering Acoustics
Identifiers
urn:nbn:se:ltu:diva-36147 (URN)879926aa-fff1-4b13-8ed3-cc3539bb5811 (Local ID)879926aa-fff1-4b13-8ed3-cc3539bb5811 (Archive number)879926aa-fff1-4b13-8ed3-cc3539bb5811 (OAI)
Note

Publikationer: Driving performance during visual and haptic menu selection with in-vehicle rotary device; Assessment of automotive visual display guidelines and principles: a literature review; A comparison of two contemporary types of in-car multifunctional interfaces; Towards a model to interpret driver behaviour in terms of mismatch between real world complexity and invested effort; Correlation between safety assessments in the driver-car interaction design process; Personalizable in-vehicle systems, technology acceptance and product attachment; Exploring user needs in automobiles; Personalizable Vehicle Interfaces for Better User Experience; What drivers really want: Investigating dimensions in automobile user needs; Design and evaluation of a personalizable interface in a vehicle contexts; Status: Ongoing; Period: 01/01/2009 → 30/06/2013

Available from: 2016-09-30 Created: 2016-09-30 Last updated: 2017-11-25Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-5435-2069

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