局域共振声子结构在汽车地毯低频隔声中的应用

Application of Locally Resonant Phononic Structures to the Low-frequency Sound Insulation of Vehicle Carpets

本文首次将局域共振声子带隙特性应用于汽车地毯的隔声设计中。基于局域共振思想,对地毯EVA隔声层进行微结构设计,使其产生一定的带隙特性,从而提高地毯的低频隔声量。理论计算和试验测试都表明,所设计的具有局域共振微结构的地毯隔声层在400Hz附近的频率范围具有局域共振声子带隙,隔声量比没有微结构的地毯隔声层提高了约5d B,说明该设计方法在低频范围突破了隔声的质量定律,利用更轻量化的材料实现了更好的低频隔声效果,为汽车低频隔声技术和轻量化设计提供了一种新的方法。

The band-gap characteristics of locally resonant phonon are applied to the sound insulation design of vehicle carpets for the first time in this paper. Based on the idea of local resonance,the microstructure of EVA sound-insulation layer of carpet is designed to endow it with certain bandgap characteristics,and hence to improve its low-frequency sound-insulation. The results of theoretical calculation and test measurement show that the sound insulation layer of carpet with locally resonant microstructure designed has a locally resonant bandgap around400 Hz,with its sound insulation increases by 5d B compared with original carpet,demonstrating that the design method adopted breaks through the mass law of sound insulation at low frequency range,and achieves a better effect of low-frequency sound insulation by using lighter material,providing a new approach to low-frequency sound insulation technique and lightweight design of vehicle.