基于赫尔姆霍尔茨共振器的活性声学元材料吸收宽带低频噪声
Reza Hedayati1, Sandhya P Lakshmanan1
1Aerospace Structure and Materials (ASM) Department, Faculty of Aerospace Engineering, Delft University of Technology (TU Delft), Kluyverweg 1, 2629 HS Delft, The Netherlands.
Materials (Basel, Switzerland)
|February 24, 2024
概括
这项研究设计和测试了使用增材制造用于减少航空航天噪音的活性声学超材料. 活性超材料在封闭式和开放式声系统中都表现出显著的声音减弱.
科学领域:
- 声学 声学 在声学方面
- 材料科学 材料科学 材料科学
- 航空航天工程 航空航天工程
背景情况:
- 航空航天应用中的噪音污染需要先进的降噪解决方案.
- 声学超材料为声音操纵提供可调节的特性.
- 赫尔姆霍尔茨共振器是有效的声学元件,用于控制噪音.
研究的目的:
- 设计和制造用于航空航天噪音降低的活性声学元材料.
- 为了研究被动和活性元材料的声衰减性能.
- 探索共振器腔深度对宽带频率性能的影响.
主要方法:
- 用64个赫尔姆霍尔茨共振器单元细胞设计一个被动的元材料.
- 增材制造用于制造被动和活性元材料模型.
- 在封闭系统 (隔音室) 和开放系统 (活性) 中进行声学测试.
- 使用步进电机来调整活动模型的执行,以调整性能.
主要成果:
- 被动元材料在150Hz (开放系统) 实现了18dB的衰减,在350Hz (封闭系统) 实现了33dB的衰减.
- 活性超材料提供了额外的10-15dB减弱 (封闭系统) 和15-20dB (开放系统).
- 可变的腔深 (10毫米和50毫米) 导致分别在515Hz和180Hz的明显衰减峰值.
结论:
- 通过增材制造制造的活性声学元材料显示出降低航空航天噪音的巨大潜力.
- 该设计允许通过可调节的共振器腔深度来减轻宽带噪声.
- 积极系统在相关的航空航天声学环境中提供了比被动配置更好的性能.
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