Sound Absorption Characteristics of Aluminosilicate Fibers Publisher



Soltani P¹ ; Mirzaei R^{2, 3} ; Samaei E⁴ ; Nourmohammadi M^{2, 3} ; Gharib S^{2, 3} ; Abdi DD⁵ ; Taban E^{2, 3} Show Affiliations
Source: International Journal of Environmental Science and Technology Published:2022

Abstract

In recent years, rapid economic development and urbanization have led to severe environmental problems such as noise pollution. The use of fibrous porous materials is considered to be an effective method to control noise pollution. This study investigates the morphological and acoustical characteristics of fibrous materials made of aluminosilicate fibers (ASFs). To this end, morphological and structural properties of samples were investigated using field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), and Brunauer–Emmett–Teller (BET) method. The effect of sample thickness and air gap was experimentally studied using the impedance tube method in the frequency range of 63–6300 Hz. The frequency-dependent acoustic behavior of the samples was also predicted using the empirical models of Delany-Bazley (D-B), Garai-Pompoli (G-P), and the proposed revised models of D-B and G-P. The XRD patterns showed that the main phases of the ASF are quartz, tridymite, and mullite. The BET analysis confirmed that the samples are classified as macro-porous. It was found that with the increase of the sample thickness sound absorption coefficient (SAC) increases at low frequencies. The averages of SACs for samples with thicknesses of 10 and 25 mm at low frequencies were 0.17 and 0.32, respectively. These values for the middle frequencies were 0.78 and 0.80, and for high frequencies were 0.83 and 0.84, respectively. Additionally, it was observed that with the increase of air gap depth, SAC enhances at low-frequency bands, and the SAC peak shifts toward the lower frequencies. Additionally, excellent agreement was observed between the experimentally measured SACs and those predicted by the revised D-B and G-P models. © 2022, The Author(s) under exclusive licence to Iranian Society of Environmentalists (IRSEN) and Science and Research Branch, Islamic Azad University.