关于膜合的海尔姆霍尔茨共振器在露天条件下的方向性
R Domingo-Roca1, A Feeney2, J F C Windmill3
1Centre for Ultrasonic Engineering, Electronic & Electrical Engineering, University of Strathclyde, Glasgow, UK. roger.domingo-roca@strath.ac.uk.
Scientific reports
|November 13, 2024
概括
研究人员使用膜合的海尔姆霍尔茨共振器开发了3D打印的声学超材料. 这些新型材料在低频率实现了显著的亚波长声音减弱,为噪声控制提供了实际的解决方案.
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
- 超材料是指一种超材料.
背景情况:
- 控制声音的吸收和扩散,特别是在低频段,是很有挑战的,因为传统的声学处理需要大量的声音.
- 现有的声学吸收器和扩散器在高频率上是有效的,但在低频应用中是不切实际的.
- 超材料提供了一种有希望的方法,通过控制设备动态来克服尺寸限制,以有效地减轻声音.
研究的目的:
- 研究3D打印的膜合的海尔姆霍尔茨振荡器 (HR) 声学元材料 (AMM) 的理论和实验性表征.
- 探索降低共振器尺寸的潜力,同时保持或改善低频声音减弱.
- 分析这些新型AMM的亚波长声学减弱能力和定向响应.
主要方法:
- 开发用于膜合HRAMM的理论数学模型.
- 使用有限元分析进行数值模拟.
- 在露天条件下对3D打印的膜合HRAMM进行实验性表征.
主要成果:
- 在理论预测和实验结果之间表现出良好的一致性.
- 通过开发的AMM,实现了显著的亚波长声学减弱 (低至λ/55).
- 观察到的定向声响应,归因于共振器大小,膜特性和双声端口的相互作用.
结论:
- 膜合的HR AMM对于重次波长声音减弱是有效的.
- 这种设计使得在紧的结构中能够有效控制低频声音.
- 这些发现为开发动态AMM为先进的宽带声衰减应用铺平了道路.
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