结构化和随机化的多孔凸尾随边缘的声学响应受到乱的边界层的影响
Elias J G Arcondoulis1, Daniele Ragni2, Daniele Fiscaletti3
1School of Civil Aerospace and Design Engineering, University Walk, Bristol BS8 1TR, United Kingdom.
The Journal of the Acoustical Society of America
|August 13, 2024
概括
结构性多孔尾随边缘 (SPTE) 显著降低了流散噪声. 这项研究表明,SPTE通过改变流放模式,在噪声抑制方面优于随机的多孔介质.
科学领域:
- 流体动力学 流体动力学
- 声学 声学 在声学方面
- 材料科学是一种材料科学.
背景情况:
- 孔隙介质附着在的尾随边 (TE) 上可以抑制流和音调噪声.
- 分析多孔介质的内部流场在实验上具有挑战性,通常需要进行数值模拟.
- 一种新的结构性多孔尾边 (SPTE) 已经开发出来.
研究的目的:
- 将SPTE的声学性能与随机的多孔介质进行比较.
- 为了研究SPTE在不同流速下减少噪音的能力.
- 为了阐明负责噪声抑制的流体物理.
主要方法:
- 进行了无声风洞实验.
- 使用声波束成型来识别噪声源.
- 一个集成区域提取了声谱.
- 波形分析检查了流流散特征.
主要成果:
- 与随机选择的多孔介质相比,SPTE表现出优异的降噪.
- 主要的声源位于固体板的末端,即使有多孔的TE.
- 波形分析显示,SPTE会破坏周期性的流失,使其变小,变宽的频率周期.
- 在流流失频率上观察到双极导向性模式.
结论:
- 在降低空气动力学噪音方面,SPTE提供了显著的优势.
- 结构化的设计有效地修改了流流动力学,以减轻噪音.
- 对SPTE流体物理学的进一步研究可以优化空气动力学噪声控制策略.
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