کاهش بومینگ نویز درون کابین خودرو با استفاده از فرامواد آوایی

Low-frequency noise, particularly the booming phenomenon, is a major challenge in vehicle cabin acoustic comfort, as traditional absorbers are inefficient at controlling it due to their required thickness and weight. This research designs and evaluates a novel acoustic metamaterial absorber, with a thickness of only 10 mm, based on a hybrid labyrinthine-Helmholtz resonator structure to control this frequency range. The proposed structure effectively absorbs long-wavelength acoustic waves through thermoviscous dissipation mechanisms by targeting specific frequencies. Numerical and experimental results, validated through impedance tube testing, demonstrate that this metamaterial can achieve a high sound absorption coefficient of over 0.7 at frequencies below 300 Hz; a performance not observed in conventional EPDM absorbers. By integrating these absorbers into the firewall of a validated numerical vehicle model, the accuracy of which was confirmed with experimental data, a reduction of 6 to 10 dB in sound pressure level was predicted at the driver's position within the booming frequency range. Consequently, this research presents a lightweight and compact solution for enhancing vehicle acoustic comfort, which simultaneously contributes to reduced weight, fuel consumption, and emissions.