噪音衰減長久以來一直是聲學工程領域中積極研究的課題。在本論文中，提出了一種新型的聲學結構，它是由具有穿孔的聲學超穎材料薄膜附加環型質量加上荷姆霍茲共振器所構成。通過使用有限元分析軟體: COMSOL Multiphysics，可以計算此結構的穿透損失、有效質量密度、速度場和薄膜位移。從結果中可以發現:與只使用聲學超穎材料的薄膜相比，添加荷姆霍茲共振器可以產生更寬的噪音衰減頻寬。若有需要不同的噪音衰減頻率，可以通過改變荷姆霍茲共振器的尺寸來實現。

Noise reduction has long been an active research subject in the field of acoustic engineering. A novel acoustic structure consisting of a perforated membrane-ring structure with a Helmholtz resonator was proposed in this thesis. The transmission loss (TL), effective mass density, velocity field and membrane displacement of the present structure are studied by using a finite element analysis software package, COMSOL Multiphysics. It is found that the addition of the Helmholtz resonator can produce a wider attenuation range compared to the use of the single membrane-type acoustic metamaterial. By altering the dimensions of the Helmholtz resonator, the desired attenuation frequency can be achieved.

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