Modified impedance tube measurements and energy dissipation inside absorptive materials
2013 (English)In: Applied Acoustics, ISSN 0003-682X, Vol. 71, no 12, 1480-1485 p.Article in journal (Refereed) Published
Impedance tube is an important tool to measure acoustic properties of a material, for which two methods have been standardized. The methods for a "modified" impedance tube have been developed recently to measure material properties in the condition of an anechoic termination. Instead of commonly used two-load or two-source methods, a method with direct and inverted configuration in cooperation with the single-microphone method is suggested in this paper. With the help of transfer matrix method, combined effect of several materials placed in series can be predicted from individual properties. A simple recurrence formula is obtained to relate the acoustic properties of a multilayer structure with the reflection and transmission coefficients of each layer. Very good agreements are obtained between the prediction and the direct measurements. Energy dissipations inside porous materials for different situations are studied and compared.
Place, publisher, year, edition, pages
2013. Vol. 71, no 12, 1480-1485 p.
Sound absorption, Impedance tube, Scattering matrix, Transfer matrix method, Direct and inverted configurations
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-131223DOI: 10.1016/j.apacoust.2013.06.013ISI: 000324227100021ScopusID: 2-s2.0-84880351638OAI: oai:DiVA.org:kth-131223DiVA: diva2:655343
QC 201310112013-10-112013-10-102013-10-11Bibliographically approved