Identification of the full anisotropic flow resistivity tensor for multiple glass wool and melamine foam samples
2013 (English)In: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 134, no 6, 4659-4669 p.Article in journal (Refereed) Published
The flow resistivity tensor, which is the inverse of the viscous permeability tensor, is one of the most important material properties for the acoustic performance of porous materials used in acoustic treatments. Due to the manufacturing processes involved, these porous materials are most often geometrically anisotropic on a microscopic scale, and for demanding applications, there is a need for improved characterization methods. This paper discusses recent refinements of a method for the identification of the anisotropic flow resistivity tensor. The inverse estimation is verified for three fictitious materials with different degrees of anisotropy. Measurements are performed on nine glass wool samples and seven melamine foam samples, and the anisotropic flow resistivity tensors obtained are validated by comparison to measurements performed on uni-directional cylindrical samples, extracted from the same, previously measured cubic samples. The variability of flow resistivity in the batch of material from which the glass wool is extracted is discussed. The results for the melamine foam suggest that there is a relation between the direction of highest flow resistivity, and the rise direction of the material.
Place, publisher, year, edition, pages
2013. Vol. 134, no 6, 4659-4669 p.
Inverse Estimation, Fibrous Materials, Absorption, Frame
Aerospace Engineering Applied Mechanics Vehicle Engineering Fluid Mechanics and Acoustics
IdentifiersURN: urn:nbn:se:kth:diva-133593DOI: 10.1121/1.4824841ISI: 000328654900009ScopusID: 2-s2.0-84890155492OAI: oai:DiVA.org:kth-133593DiVA: diva2:662345
FunderEU, European Research Council, MRTN-CT-2006-35559
QC 201401212013-11-062013-11-062014-01-21Bibliographically approved