Investigation into the sound absorptivity of perforated panels with tapered hole geometries coupled with polyurethane foam

This investigation explores the improvement of acoustic properties in perforated panels enhanced with polyurethane foam for architectural and environmental noise reduction. Employing the Box Behnken design methodology, it scrutinises the influence of perforation geometries and the integration of porous materials on sound absorption across a frequency spectrum of 100–4000 Hz. The study investigates the interplay between panel design and material characteristics through detailed acoustic analysis, including sound absorption coefficient (SAC) and noise reduction coefficient (NRC) measurements. Finite element analysis, conducted with COMSOL Multiphysics 6.1, and impedance tube tests aligned with ISO 10534-2 standards assessed fifteen unique perforated panel configurations produced via a Markforged 3D printer using onyx material. The research reveals that panels with tapered holes and polyurethane foam significantly enhance acoustic performance, surpassing traditional materials in low to mid-frequency ranges. The congruence of experimental results with finite element analysis simulations validates the computational approach, highlighting the importance of geometric and material optimisation in acoustic design. This work provides actionable insights and guidelines for optimal acoustic solutions, marking a step forward in the pursuit of advanced noise control and acoustic environment enhancement.