Sound absorption of a micro-perforated plate backed by a porous material under high sound excitation: measurement and prediction

Abstract

The sound absorption coefficient of perforated facings backed by porous materials is studied under high sound intensities in the absence of mean flow. The theoretical considerations are based on the equivalent fluid following the Johnson-Champoux-Allard approach and the use of the transfer matrix method. To take into account the high sound levels effects, the air flow resistivity of each layer is modified following the Forchheimer law. Two specimens of perforated plate are built and tested when backed by a polymeric foam and a fibrous material. A specific impedance tube setup is developed for the measurement of the surface acoustic impedance for sound pressure levels ranging from 90 dB to 150 dB at the surface of the perforated facing. To corroborate the validity of the presented method, two considerations are particularly depicted in the experimental results: first, the case where the perforated facing and the porous material are both directly backed by a rigid wall and the case where there is an air cavity between the porous material and the rigid wall. Good agreement is observed between the simulation and the experimental results.

Aeroacoustic near-field measurements with microscale resolution

“…Furthermore, the sensor offers perspectives for aeroacoustic investigations of e.g. micro-perforated liners [37].…”

Time-domain simulation of the acoustic nonlinear response of acoustic liners at high sound pressure level

“…Basic examples of other studied absorbent materials are double degree of freedom liners [Gautam et al, 2022], perforated plates backed by a porous medium [Tayong et al, 2013, Peng, 2018 or porous materials alone [Cao et al, 2018]. The latter is usually a two-phase medium with a solid skeleton filled by a fluid (air herein) by means of pores of relatively small size.…”

Acoustic metamaterial composed of zigzag channel and micro-perforated plate for enhanced low-frequency sound absorption

“…In recent years, the emergence of acoustic metamaterials (AMMs) (Climente et al, 2012; Lu et al, 2020; Li et al, 2020; Laly et al, 2022) provides new possibilities for the fabrication of low-frequency noise absorbers (Zhang et al, 2017; Yang and Sheng, 2017; Wu et al, 2016). Many subwavelength noise-absorbing materials are progressed based on resonant metamaterials, including Helmholtz resonators (HRs) (Ma et al, 2014; Kim and Lee, 2014; Yu et al, 2017; Jung et al, 2018), and micro-perforated plate absorbers (MPAs) (Buret and Iu, 2012; Tayong et al, 2013; Tao et al, 2014; Liu et al, 2021), which simplifies the design and fabrication and has high absorption efficiency that can be tuned by adjusting the structure but not limited by the constituent materials (Kumar et al, 2020; Nguyen et al, 2020; Qian et al, 2017; Sakagami et al, 2009). For instance, Hong et al presented a Helmholtz resonator with variable helical structure, which changes the acoustic impedance of the absorber to improve its performance (Hong et al, 2022).…”