Acoustic properties of eco-friendly Micro-Perforated Panel (MPP) incorporating animal fibers

Micro-perforated panels (MPPs) are innovative alternatives to traditional sound-absorbing materials, though they exhibit limitations in efficiency at high frequencies, rendering them unsuitable for interior wall finishes. Enhancing their performance involves incorporating porous materials into the air gap. Natural materials, like sheep, goat, and camel wool, are emerging as sustainable substitutes for synthetic sound insulators. This study assessed the sound absorption coefficients of wool-based insulating materials and analyzed MPPs backed by wool composites of varying thickness using an impedance tube per ISO ۱۰۵۳۴-۲. The impact of pore shape, perforated plate thickness, and wool composites in the air gap were investigated. Results re-vealed that camel wool demonstrated the highest sound absorption performance, achieving a maximum ab-sorption coefficient of ۰.۹۵ at frequencies above ۱۰۰۰ Hz. The maximum sound absorption coefficient of MPPs generally occurs in the medium frequency range (۸۰۰-۱۵۰۰ Hz), shifting to lower frequencies with increased panel thickness without altering the absorption bandwidth. Similarly, sugarcane fiber composites with varying thicknesses showed that a ۱ cm-thick wool composite reached a peak SAC of ۹۵% at ۳۵۰۰ Hz, shifting to lower frequencies as thickness increased. Importantly, the pore shape and porosity did not signifi-cantly affect SAC, highlighting the limited impact of these factors. The incorporation of wool composites in the air gap notably enhanced SAC and broadened the absorption bandwidth, particularly at lower frequen-cies. However, this enhancement came at the cost of reduced SAC at higher frequencies, making MPPs with wool composites unsuitable for managing sounds above ۳۰۰۰ Hz. Nonetheless, MPPs backed by wool com-posites provide an environmentally responsible option for low-frequency sound management. Their reduced ecological footprint and improved acoustic performance at lower frequencies underscore their potential for sustainable acoustic solutions This study highlights the viability of integrating natural materials like wool into acoustic designs, achieving both superior sound absorption and sustainability. By focusing on lower-frequency sound control, MPPs with natural backing materials emerge as a promising alternative in the field of eco-friendly acoustic engineering.

کلیدواژه ها:

Micro-Perforated Panel ، MPP ، noise ، adsorption