Sound absorption properties of functionally graded polyurethane foamsInternoise (2012)
AbstractNoise control over a wide frequency band is an increasingly important design criterion in the building and transport industries. Examples of well known broadband passive concepts for optimal sound absorption are multi-layering with graded properties across the thickness and optimization of the material shape (e.g., wedges). However, for typical applications, the material thickness is limited and shaping or use of different material costly. Thus, there is growing interest for developing acoustical materials having microstructure properties gradient at the micro- or meso-scale; also known as Functionally Graded Materials (FGM). Even if sophisticated models are available to predict the acoustic behavior of homogeneous and multilayered acoustical materials, there is still a need for a better understanding of FGM for sound absorption. More specifically, does a graded foam material always improve the acoustic behavior compared to a homogeneous one? This presentation proposes to answer this question by investigating numerically, using a microstructure model, the effect of varying the reticulation rate along the thickness of a highly porous polyurethane foam.
Publication DateSummer August, 2012
Citation InformationOlivier Doutres and Noureddine Atalla. "Sound absorption properties of functionally graded polyurethane foams" Internoise (2012)
Available at: http://works.bepress.com/olivier_doutres/34/