@ARTICLE{Alba_Jesus_An_2011, author={Alba, Jesus and del Rey, Romina and Ramis, Jaime and Arenas, Jorge}, volume={vol. 36}, number={No 3}, journal={Archives of Acoustics}, pages={561-574}, howpublished={online}, year={2011}, publisher={Polish Academy of Sciences, Institute of Fundamental Technological Research, Committee on Acoustics}, abstract={Characterization of sound absorbing materials is essential to predict its acoustic behaviour. The most commonly used models to do so consider the flow resistivity, porosity, and average fibre diameter as parameters to determine the acoustic impedance and sound absorbing coefficient. Besides direct experimental techniques, numerical approaches appear to be an alternative to estimate the material's parameters. In this work an inverse numerical method to obtain some parameters of a fibrous material is presented. Using measurements of the normal incidence sound absorption coefficient and then using the model proposed by Voronina, subsequent application of basic minimization techniques allows one to obtain the porosity, average fibre diameter and density of a sound absorbing material. The numerical results agree fairly well with the experimental data.}, type={Artykuły / Articles}, title={An Inverse Method to Obtain Porosity, Fibre Diameter and Density of Fibrous Sound Absorbing Materials}, URL={http://www.czasopisma.pan.pl/Content/104435/PDF/06_paper.pdf}, doi={10.2478/v10168-011-0040-x}, keywords={sound absorption, fibrous materials, porous material, material characterization}, }