Applications of acoustic waveguide device with graded phononic crystal

梯度聲子晶體聲波導元件之設計與應用

葉佳益(Jia-Yi Yeh) ； 陳俊宇(Jiun-Yeu Chen)

《中華民國振動與噪音工程學會論文集》 2018 (2018/06) Pp. 54-57

摘要

The present paper is to investigate the characteristics graded phononic crystals with smart material. The acoustic waveguide characteristic of the graded phononic crystals is utilized to design some novel acoustic devices by combining system with graded phononic crystals structure. The graded phononic crystal is composed of circular cylindrical with air background in this proposal. The effective refractive index can be tuned by adjusting the filling ratio because that periodic structure behaves like a homogeneous medium, since dispersion relation is almost linear in long wavelength limit assumption. The plane wave expansion method is used to calculate the band structures of the graded phononic crystal and obtain the effective refractive index of the graded phononic crystal with various filling rations. The graded phononic crystal with smart materials can be used to design more effective acoustic waveguide devices and it also can be applied to investigate other types of graded phononic crystal devices with various smart materials in future studied based on the numerical and experimental results of this proposal.

關鍵字

graded phononic crystal ； smart material ； tunable ； acoustic waveguide

並列摘要

本計畫目的在於分析具梯度材料特性分布之聲子晶體聲波導結構的特性應用，並能夠結合可藉由特定外加因子來調變材料特性的智能材料，能夠設計出優於一般單純傳統聲波導的元件設計與應用範圍。首先針對聲子晶體聲波導的材料梯度分布特性進行分析，使用平面波展開法求得聲子晶體的色散曲線，並利用色散曲線計算不同填充比下的聲子晶體等效折射率。而後再結合梯度分佈特性的結構設計，針對具有梯度分佈的週期性聲子晶體結構進行分析，讓所設計的梯度聲子晶體聲波導元件結構具備有一般均質材料無法輕易得到的應用層面，未來希望能藉由此類的研究來設計出全新的聲波導元件，而更可以藉著本計畫的研究，樹立一套設計的範本，以利於往後在光波、聲波、電磁波與力學之間的統合設計應用。

並列關鍵字

梯度聲子晶體 ； 智能材料 ； 可調式 ； 聲波導