Acoustique

Chaine de l'institut Le Mans Acoustique

http://lemans-acoustique.fr/fr/innovation.html 

 

Noise Reducing Materials and Structures

Relationship between sound absorption property and transmission behavior of Struto nonwoven, by Tao Yang (Technical University of Liberec)

Jan. 25, 2017
00:10:49
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DENORMS Action’s Workshop “Modelling of high performance acoustic structures Porous media, metamaterials and sonic crystals”, Rome, 24-25th January 2017

Website of DENORMS Action

Programme of the Workshop

Session on Use of metamaterials in other fields of Physics and metamaterials exposed to multiple physical phenomena

Speaker: Tao Yang (Technical University of Liberec)

Abstract:

This study presents an experimental investigation on the sound absorption behaviour and thermal properties of struto nonwovens by establishing relationship between these properties. Seven Struto nonwoven fabrics were selected to examine noise reduction coefficient (NRC) and average values of sound absorption coefficients (a) as well as thermal properties including thermal conductivity and thermal resistance. The Brüel and Kjær impedance tube instrument and Alambeta were used for evaluation of acoustic and thermal properties, respectively. The influence of structural parameters on acoustic and thermal properties of Struto nonwovens were investigated and analyzed. The results showed that Sturo nonwovens with higher thickness, finer fibres and higher fabric grams per square meter can provide better sound absorption performance. The effect of specific airflow resistance on sound absorption performance was also investigated. It is observed that sound absorption performance has a strong correlation with specific airflow resistance. The effect of porosity on specific airflow resistance and thermal properties was studied in detail. The result indicated that porosity has a strong correlation with specific airflow resistance and thermal properties. It was also observed that sound absorption, the NRC and a, have insignificant correlation with thermal conductivity, while they are strongly correlated with thermal resistance. The correlation coefficient of NRC with thermal resistance is 0.9835, indicating that NRC is directly proportional to thermal resistance of Struto nonwovens.