貼附吸音材料共鳴型消音器之最佳化設計

Optimum Design of Resonator With Absorbent Materail

陳嘉宏(Jia-hong Chen)

指導教授 ： 張英俊

大同大學/工程學院/機械工程學系所/碩士(2010年)

摘要

本篇論文主要分析共鳴管在膨脹腔內放入多孔性材料之聲學性能，利用平面波理論，推導其傳輸矩陣。聲波傳遞在多孔性材料中相當複雜，對材料吸音係數而言，流動阻力是最重要的因素，利用Allard的理論，經由數值解耦合方法解決聲波傳遞與流動阻力複雜問題。
爾後將各元件與文獻驗證求其正確性，證實本文所採用之各個元件使用的傳輸矩陣理論無誤，並對消音器做性能分析。本文主要針對共鳴型消音器空腔內放入吸音材料，提升消音性能。結合遺傳演算法（Genetic algorithm, GA）之最佳化方法，針對單一頻率搜尋消音器之最佳化尺寸及聲音傳輸損失，使其達到最佳消音性能。
結果顯示出，每個消音器針對單一頻率尺寸最佳化後，其消音性能均有顯著提升。

關鍵字

多孔性材料 ； 最佳化設計 ； 遺傳演算法 ； 消音器

並列摘要

The purpose of this study analyzed the the acoustic properties of cavity resonance tube with porous materials. Using plane wave theory to infer its transfer matrix. The Sound wave propagation in the porous material is really complicated, for absorbent material, flow resistance is the most crucial factor. Adopting Allard’s theory, the present study solved the problem of sound wave propagation and flow resistance with coupling numerical method.
It shows that the theorem of transfer matrix is correct by comparing them with the previous literature before it was used to analyzed the performance of muffler. The main purpose of this study try to find out the improvement in silencer after putting porous material in resonators the expansion chamber. Using the optimal design of Genetic algorithm (GA), the best silencer performance was achieved.
The result indicated that there was a significant improvement in the performance of silencer after optimizing each design method of each muffler.

並列關鍵字

Optimal design ； genetic algorithm ； mufflers ； porous material

參考文獻

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