日常生活中總是充斥著許多噪音，各種惱人的聲音不斷造成聽覺干擾，然而人們通常喜歡待在相對安靜的環境。如果在室內或是較為封閉的空間內，就能借助設有阻尼器並以彈性材質製成的牆或邊界來降低噪音。而這種空氣流體和固體結構的耦合系統及交互作用可以藉由流固互制問題的數學模型來模擬，應用有限元素法離散化之後，將其其轉換為等價的二次特徵值問題即可求得數值解。特徵值可反映出耦合系統的物理性質，其中我們選擇觀察在工業和科學領域中較被關注的低頻率特徵值。而後可經由數值模擬的結果來選擇消音材質或阻尼器的設置地點，以適應各種不同的情況及需求。

Noise is all around us. We are disturbed by these unpleasant sound all the time. However, most of the time people prefer to stay in a quieter environment. If people stay in enclosed space, we can keep the noise down by the aid of the boundaries which is made by elastic material, and furthermore set a damper on it to enhance the efficiency. The coupling and the interaction between fluid and structure can be simulated by a mathematical model called the acoustic structure interaction problem. It can be transform into a equivalent quadratic eigenvalue problem by applying the Galerkin finite element method. Eigenvalues reflects the behavior of the couple system, among these eigenvalue, we are interested in finding the low frequency eigenvalues which are concerned in the field of industrial and science. By the numerical simulation, the choices of material and the position of damper can be adjusted according to different situations or requirements.

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