振動以及噪音汙染在現今的社會中已經是一項無法忽視的重大問題，如何有效隔離抑或是消除噪音為學業界近年致力解決的一大工程。本研究由推導聲波方程式配合阻抗匹配法以計算共振腔在各頻率下之吸音率曲線，並以等效介面方式計算介面之聲阻抗，並延伸推導不同模型，並對其求出合適之截面比；其減噪機制為共振腔在其共振頻率由於空氣高速流通下熱黏滯耗損聲能，而產生高度的吸音率。
設計完模型後，再以有限元素模擬軟體COMSOL Multiphysics計算理想情況中共振腔在各頻率之吸音率，引入有效長度修正項，以曲線擬合之方式求得其值；而本篇研究有限元素模擬直管對阻抗匹配理論之修正項幾乎皆為0.35。
模型之設計也延續蜷曲式共振腔吸音薄板之概念結合如等效電路、精簡幾何等方式以拓展頻寬、提高吸音薄板之空間使用率，節省材料之同時提高吸音效果，並運用三維列印的高客製性進行製作，實驗上各模型都有最高達0.9以上之吸音率，雖然僅在有限頻寬才有此高度吸收率，卻是常見之吸音多孔性材料難以企及。實驗上和有限元素模擬仍存如蜷曲管以及三維列印造成粗糙度之差異，使得修正項有所差異，但頻寬以及吸音率曲線趨勢仍可透過使用合適之修正項而疊合(實驗大部分修正項為0.15)，驗證能以阻抗匹配理論預測吸音薄板吸音率之曲線趨勢。

Vibration and noise pollution have become a problem that cannot be ignored. How to effectively isolate or eliminate noise becomes a major research subject nowadays. In this study, the impedance matching method and finite element method are used to capture the sound absorption of the thin panel with a resonant cavity. The noise reduction mechanism is attributed to the thermal and viscous loss of acoustic energy as the resonant behavior of the cavity occurs. The resonant cavity of the sound absorbing panel is coiled up for space-save purpose. The 3D printing technique is utilized to fabricate the designed structure. The experimental results show that the sound absorption of the present panel is up to 0.9 or higher. With the proper correction of the tube length, the numerical results obtained by impedance matching method can perfectly match the ones obtained by experiments.

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