噪音一直是人們日常生活中非常棘手的問題，為了擁有更好的生活品質，因而發展出了各式各樣預防噪音的設計。本研究結合四分之一波長共振腔與中心穿孔且表面附加環形質量之薄膜型超穎材料，設計出一種新型的混合型諧振器，其減噪機制與亥姆赫茲諧振器相似。當聲音在此結構中傳遞時，特定頻率下透射的聲波很少，會發生較大的穿透損失，因而達到降噪的效果。與傳統的四分之一波長共振腔相比，這種新型混合型諧振器減噪的頻率發生在較低頻的位置，並且可產生額外的減噪頻率，透過尺寸設計能調整減噪發生的頻率位置，而孔洞與環形質量的尺寸是影響減噪頻率重要的因素之一。除了減噪外，本研究進一步地將壓電片貼附於無中心孔洞的混合型諧振器之薄膜表面上，使結構能達到同時實現降低噪音與擷取能量的目的。壓電片透過形變產生電壓，因此透過設計與改良結構中的薄膜形超穎材料增加壓電片的變形量，能更有效地將能量轉換為電能輸出。
本研究使用COMSOL多物理耦合軟體進行模擬分析，透過軟體計算出穿透損失、電壓、電功率以及能量轉換效率之頻率響應圖，針對100Hz到1500Hz頻率範圍討論新型混合型諧振器的降噪與擷能行為。

Noise has been a very difficult problem to solve in our daily life. In order to have a better quality of life, a variety of noise isolation designs have been developed. In this thesis, a new type of hybrid resonator is presented. This new design consists of a membrane-orifice-ring metamaterial backed by a closed air cavity. The noise reduction mechanism in such a structure is similar to that of a Helmholtz resonator. Compared to conventional quarter-wave resonators, this novel structure can produce an extra transmission loss peak and significantly lower down the peak frequency. Varying the geometric properties of the metamaterial enables to adjust the frequency band where sound is attenuated. In addition to noise reduction, the present study further investigates the energy harvesting capability of the membrane-ring-central-mass structure backed by an air cavity. The piezoelectric patch is attached to the back surface of the membrane surface. At transmission loss peak, the piezoelectric patch deforms and generates electricity. The proposed design can be used for filtering noise as well as harvesting energy.

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