Acoustic metamaterials can control, direct, and manipulate sound waves, hence, they attract more researchers’ attention in the field of automotive, aerospace, and architecture to reduce noise levels. Here, vehicle exhaust noise is investigated through finite element simulation. In this study, an improved muffler is proposed to affect the transmission loss. In the case of acoustic performance, we first designed the acoustic metamaterial baffles (AMBs) with locally resonant structures in order to reduce the noise level in the desired frequency range; a desired frequency range was targeted to be affected by tuned resonators. For describing AMBs, four models were designed to obtain transmission loss peaks and stop-band behavior at the dual-target-frequency range. Hence, in order to prove the effectiveness of the proposed muffler, they were compared with conventional mufflers. Results indicated that AMBs improve the muffler transmission loss by up to 89 dB. The combination of resonators and their configurations, as well as spacing of the AMBs, play a significant role in affecting the transmission loss peak. At the end, to observe and show the actual performance of the proposed acoustic metamaterial muffler, essential aspects like pressure drop and flow are obtained using computational fluid dynamics (CFD) software, and highly reasonable and realistic results are achieved.

声学超材料可以控制、引导和操纵声波，因此它们在汽车、航空航天和建筑领域以降低噪声水平吸引了更多研究人员的关注。在这里，通过有限元模拟研究车辆排气噪声。在这项研究中，提出了一种改进的消声器来影响传输损耗。在声学性能方面，我们首先设计了具有局部谐振结构的声学超材料挡板（AMB），以降低所需频率范围内的噪声水平；期望的频率范围旨在受调谐谐振器的影响。为了描述 AMB，设计了四个模型来获得双目标频率范围内的传输损耗峰值和阻带行为。因此，为了证明所提议的消声器的有效性，它们与传统的消声器进行了比较。结果表明，AMB 将消声器传输损耗提高了 89 dB。谐振器及其配置的组合以及 AMB 的间距在影响传输损耗峰值方面起着重要作用。最后，为了观察和展示所提出的声学超材料消声器的实际性能，使用计算流体动力学 (CFD) 软件获得了压降和流量等基本方面，并获得了高度合理和现实的结果。