轻薄宽带声学超构材料吸声性能与拼接

Large Broadband Sound Absorption Performance and Splicing Application of Acoustic Metamaterials with Lightweight Design Configurations

摘要:

针对传统声学材料难以有效吸收中低频噪声以及声学超构材料轻薄化宽带应用问题，基于声学超构单元耦合共振吸声原理和并联阻抗匹配设计理论，提出一种嵌入管式声学超构模块和航空棉模块并联交替组合的声学超构组件构型与大幅面拼接应用设计方案，实现了优良的低宽频吸声性能。首先利用差分进化算法优化设计出厚度仅为13.98mm的中低频声学超构吸声模块。然后基于声电类比等效电路，反演构建了声学超构模块与航空棉并联组合的声阻抗与吸声系数理论模型，解析和实验验证了其良好的低宽频吸声性能。最后以交替拼接方式拓展制备了大幅面声学超构材料样件，实验结果表明，其在500~8 000Hz宽频带内平均吸声系数高达0.92，等效面密度仅为2.87kg·m^-2。针对高端装备制造、新能源汽车等战略新兴产业中有限夹层空间内的低宽频降噪应用难题，该声学超构材料具备轻薄化、宽带高吸声与拼接装配便捷等应用优势。

Abstract:

To address the challenges of traditional acoustic materials in effectively absorbing mid-low frequency noise and the lightweight， broadband application issues of acoustic metamaterials， this paper proposes a design scheme for an acoustic metamaterial component configuration that combines an embedded tubular acoustic metamaterial module with an aviation cotton module in a parallel alternating arrangement. This design achieves excellent low-frequency broadband sound absorption performance. First， a sound-absorbing module for mid-low frequency acoustics with a thickness of only 13.98 mm was optimized and designed using a differential evolution algorithm. Then， based on the acoustic-electrical analogy equivalent circuit， a theoretical model for the sound impedance and sound absorption coefficient of the parallel combination of the acoustic metamaterial module and aviation cotton was constructed and verified through analysis and experiments， demonstrating its good low-frequency sound absorption performance. Finally， large-sized acoustic metamaterial samples were prepared using an alternating splicing method. Experimental results indicate that the average sound absorption coefficient within the 500~8 000 Hz broadband reaches as high as 0.92， with an equivalent surface density of only 2.87 kg·m^-2. This acoustic metamaterial offers advantages such as lightweight， broad bandwidth high sound absorption， and convenient splicing assembly， addressing the low-frequency noise reduction challenges in the limited sandwich space of strategic emerging industries like high-end equipment manufacturing and new energy vehicles.