本文藉由有限元素模擬分析固—流組合而成之二維聲子晶體波傳特性，並以聲音衰減量呈現聲子晶體發生頻溝之頻帶。首先模擬Sánchez-Pérez等人研究由不鏽鋼作為填充體，空氣作為母材之二維聲子晶體有限元素模型，證實本模擬的可行性，並進行全頻寬之實驗量測與數值模擬；接著以實驗搭配模擬分析填充率5％與10％之正方晶格與填充率10％之六角晶格聲子晶體，綜合[100]與[110]方向入射之結果，可計算求得全頻溝發生之區間。
本研究成果已成功建立有限元素模擬分析固—流組合成之二維聲子晶體模型，經由比對文獻結果和本實驗結果已驗證模擬之可行性與準確性，這將說明有限元素法可成為未來聲子晶體在設計成為新型吸（隔）音材的一項有利分析工具之一。

In this work we apply the finite element method to analyze the wave transmission property of solid/fluid composite medium, phononic crystal. The sound attenuation spectrum is obtained to show the forbidden bands of the band gap. First, we construct the finite element model for a two-dimensional phononic crystal, studied by Sánchez-Pérez etc. with PWE and experimentally, constituted of a rectangular array of parallel circular stainless steel cylinders in air. It has demonstrated that our simulation work was feasible; then, we performed the experimental measurements and simulations by using the narrow and wide frequencies. The results show agreement between the experiments and the simulations. We also simulated the crystal samples of filling fraction 5 % and 10 % for square and hexagon lattice, respectively, in both the [100] and [110] direction. The full band gaps are determined from the combination of the results.
We have investigated the finite element simulation for the solid/fluid phononic crystal successfully. Both work the results of experiment in the reference and in this work are compared with the FEM simulation. It demonstrates that the finite element method is a good tool for the design of phononic crystal in application to new type sound absorption (isolation) material.

中文摘要 I
英文摘要 II
目錄 III
表目錄 VI
圖目錄 VII
第一章 緒論 1
1-1前言 1
1-2文獻回顧 3
1-3研究動機與目的 5
第二章 基本理論 7
2-1 聲子晶體相關理論 7
2-1-1 二維晶格種類 7
2-1-2 晶體晶格與倒晶格（Reciprocal Lattice） 8
2-1-3 填充率（Filling Fraction） 9
2-1-4 布拉格定理（Bragg Law） 10
2-1-5 布里淵區（Brillouin Zone） 13
2-1-6 [100]與[110]方向指數 14
2-1-7 頻溝產生的機制 16
2-2 有限元素法原理 17
2-2-1有限元素法概述 17
2-2-2 以有限元素模擬水中聲場變化 17
2-2-3 流/固耦合作用 21
2-2-4 有限元素軟體介紹與處理步驟 22
2-2-5 使用元素介紹 23
第三章 數值模擬方法及步驟 39
3-1 模擬目的 39
3-2 模擬設定及步驟 40
3-2模擬數據處理 49
第四章 實驗設定與架構 54
4-1 實驗目的 54
4-2 二維聲子晶體製作 54
4-3 二維聲子晶體實驗設備 55
4-4 實驗設定與架構 58
4-5 探頭遠場的安置 59
第五章 實驗與模擬結果 74
5-1 數值模擬與文獻實驗比對 74
5-2 數值模擬與實驗之單頻與全頻寬結果比較 75
5-3 數值模擬與實驗之比較與分析 77
5-4 數值模擬計算全頻溝 79
第六章 結論與未來研究方向 98
6-1結論 98
6-2 未來研究方向 99
參考文獻 101

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