Sound Absorption Measurements and Numerical Estimation of Non Acoustical Parameters of some Moroccan Raw Green Materials

Abstract:

Knowledge of acoustical properties of granular and fibrous sustainable materials has been stimulated thanks to their rather easy handling and durability. In this work direct measurements of the normal incidence sound absorption coefficient of three non consolidated materials (esparto fibers, cork and perlite) have been carried out using the so-called transfer function method. These materials are plentiful in Morocco and they require low amounts of energy for processing, which makes them attractive as either thermal insulating or sound absorbing materials. Results show that the acoustical efficiency of studied materials is comparable to traditional materials. In addition, an inverse estimation of non acoustical parameters (flow resistivity, tortuosity and porosity) of these materials has been performed introducing a new predictability approach. This is based on Global Sensitivity Analysis combined with Global Numerical Optimization Techniques, regarding most usual mathematical models.

• Periodical: Advanced Materials Research (Volume 1051)
• Pages: 95-101
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1051.95
• Online since: October 2014
• Authors: Mohammed Garoum*, Chaimaa Benayad
• Keywords: Air Resistivity, Alfa, Cork, Perlite, Porosity, Sound Absorption, Sustainable Materials, Tortuosity

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