单层丝和棉花织物用于声波发射和主动压制声音的织物
Grace H Yang1, Jinuan Lin2, Henry Cheung3
1Department of Chemical Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA, 02139, USA.
Advanced materials (Deerfield Beach, Fla.)
|April 1, 2024
概括
这项研究表明,使用压电驱动器,丝织物可以发出高达70dB的声音,并抑制75%的噪声. 织物特性影响声音控制,在各种行业中提供应用.
科学领域:
- 材料科学 材料科学 材料科学
- 声学 声学 声学 声学
- 织工程 织工程 织工程
背景情况:
- 在从服装到建筑的应用中,声音控制至关重要.
- 传统面料的声学特性被探索.
- 压电驱动器为声音操纵提供了新的方法.
研究的目的:
- 调查传统织物,特别是丝的使用,作为发射和抑制声音.
- 分析织物结构 (孔隙大小) 与声辐射效率之间的关系.
- 用两个不同的机制来证明和量化声音抑制.
主要方法:
- 将丝织物连接到压电纤维执行器,以测量声音发射.
- 使用振动仪测量来分析织物行为.
- 进行比较性织物分析,以将毛孔大小与声效率相关联.
- 实施直接的声学干扰和振动介导的抑制,以减弱声音.
主要成果:
- 丝织物发出高达70dB的声音,表现得像一个薄板.
- 声波发射效率受到织物孔径大小相对于粘性边界层的影响.
- 通过声学干扰实现了高达37dB的声音抑制.
- 以振动为媒介的抑制将振动幅度降低了95%,并将声音减弱了高达75%.
- 声学反射率是动态控制的,增加了高达68%.
结论:
- 丝织物,特别是厚度为130微米的丝织物,在噪声发射和控制方面具有显著的潜力.
- 织物孔径大小是声波排放效率的一个关键因素.
- 声音抑制的双重机制提供了多样化的应用.
- 声学反射率的动态控制为智能材料设计开辟了新的途径.
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