應用遺傳演算法於室內聲場之最佳化設計

Application of Genetic Algorithm in the Optimal Design of Interior Sound Field

李秦宇(Chin-yu Li)

指導教授 ： 張英俊

大同大學/工程學院/機械工程學系所/碩士(2005年)

摘要

本論文結合遺傳演算法(Genetic algorithm, GA)與聲學分析軟體SYSNOISE於室內聲場之最佳化設計。在SYSNOISE分析中，場點(Field point)模擬麥克風量測位置，以邊界元素法(Boundary element method, BEM)得到聲音/噪音分貝值(Sound pressure level)。論文分為三個部份：一、三維聲場之音源最佳配置：搜尋五個音源最佳位置與音量使每個場點盡可能為聲音分貝期望值80dB；二、三維聲場之噪音防治：搜尋吸音材料最佳配置以降低特定場點噪音；三、音源辨認：使用遺傳演算法辨認音源位置與音量。
第一部份分析結果顯示教室之場點聲音分貝範圍控制在72.3 ~ 87.0dB。第二部份分析結果顯示以六位工作人員位置為場點，噪音控制前場點噪音分貝範圍為99.8dB ~ 108.6dB，其均方根值為104.49dB；噪音控制後場點噪音分貝範圍為48.0dB ~ 106.5dB，其均方根值為91.23dB，噪音降低13.26dB。第三部分顯示遺傳演算法準確地同時辨認三音源三維位置與音量。

關鍵字

最佳化設計 ； 邊界元素法 ； 聲場 ； 吸音材料 ； SYSNOISE ； 遺傳演算法

並列摘要

n this thesis, combining genetic algorithm (GA) with acoustic analysis software SYSNOISE is proposed to the optimal design in interior sound field. Field points simulate measuring points of microphones. The sound pressure level (SPL) is obtained by boundary element method (BEM) in SYSNOISE. This thesis divides into three parts: (1) Optimal sound source placement in 3-D interior sound field: SPL of all field points are expected to be 80dB by searching optimal positions and volume of five sound sources. (2) Noise reduction in 3-D interior sound field: searching the optimal placement of sound absorbing materials for noise reduction of specific field points. (3) Noise source identification: identifying positions and volume of noise sources by GA.
The results of the first part results show that the SPL of the field points in classroom is 72.3dB ~ 89.0dB under five sound sources control. The results of the second part results show that the SPL of the field points is 99.8dB ~ 108.6dB and the root mean square value is 104.49dB before noise control; the SPL of the field points is 48.0dB ~ 106.5dB and the root mean square value is 91.23dB after noise control. The noise reduction is 13.26dB. The results of the third part results show that GA has the capability to identify positions and volume of three noise sources accurately at the same time.

並列關鍵字

BEM ； boundary element method ； GA ； genetic algorithm ； optimal design ； sound absorbing material ； sound field ； SYSNOISE

參考文獻

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