The primary noise sources of the vehicle are the engine, exhaust, aeroacoustic noise, and tire–pavement interaction. Noise generated by the first three factors can be reduced by replacing the combustion engine with an electric motor and optimizing aerodynamic design. Currently, a dominant noise within automobiles occurs from the tire–pavement interaction over a speed of 70–80 km/h. Most noise suppression efforts aim to use sound absorbers and cavity resonators to narrow the bandwidth of acoustic frequencies using foams. We demonstrate a technique utilizing acoustic metasurfaces (AMSes) with high reflective characteristics using relatively lightweight materials for noise reduction without any change in mechanical strength or weight of the tire. A simple technique is demonstrated that utilizes acoustic metalayers with high reflective characteristics using relatively lightweight materials for noise reduction without any change in mechanical strength or weight of the tire. The proposed design can significantly reduce the noise arising from tire–pavement interaction over a broadband of acoustic frequencies under 1000 Hz and over a wide range of vehicle speeds using a negative effective dynamic mass density approach. The experiment demonstrated that the sound transmission loss of AMSes is 2–5 dB larger than the acoustic foam near the cavity mode, at 200–300 Hz. The proposed approach can be extended to the generalized area of acoustic and vibration isolation.
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机译:车辆的主要噪声源是发动机,排气,喷气沟噪声和轮胎路面相互作用。通过用电动机更换燃烧发动机和优化空气动力学设计,可以减少前三个因素产生的噪音。目前,汽车内的主导噪音发生在速度为70-80 km / h的速度下的轮胎路面相互作用。大多数噪声抑制力旨在使用声音吸收器和腔谐振器使用泡沫缩小声学频率的带宽。我们展示了一种利用具有高反射特性的声学元件(AMSES)的技术,使用相对轻质的材料进行噪声降低而没有机械强度或轮胎重量的任何变化。证明了一种简单的技术,其利用具有高反射特性的声学金属层,使用相对轻的材料进行噪声降低而没有任何变化的机械强度或轮胎重量的变化。所提出的设计可以显着降低轮胎路面在1000 Hz下的宽带声频相互作用上产生的噪音,以及使用负有效的动态质量密度接近的广泛的车速。实验表明,200-300Hz,AMSES的声音传输损失比腔模式附近的声学泡沫大2-5dB。所提出的方法可以扩展到声学和振动隔离的广义区域。
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