在不断变化的横截面积管道中,威利斯合器
A Krpenský1, M Bednařík1, J-P Groby2
1Faculty of Electrical Engineering, Department of Physics, Czech Technical University in Prague, Technická 2, 166 27 Prague 6, Czech Republic.
The Journal of the Acoustical Society of America
|September 13, 2023
概括
这项研究使用先进的同质化技术在不对称管道中获得了声波传播的有效特性. 第二阶方法,包括威利斯合,为工程应用提供更广泛的频率有效性.
科学领域:
- 声学 声学 在声学方面
- 波浪传播 波浪传播
- 材料科学 材料科学 材料科学
背景情况:
- 了解复杂介质中的声波行为对于设计先进的声学设备至关重要.
- 周期结构提供了独特的波浪操纵特性,但不对称性引入了复杂性.
- 有效的介质理论简化了在异质材料中波传播的分析.
研究的目的:
- 从理论和数值上推导出声波在一维周期和不对称管道中传播的有效性质.
- 开发有效性质的闭式表达式,包括不对称的威利斯合.
- 为了比较一级和二级同质化程序的有效性和性能.
主要方法:
- 使用Peano-Baker系列扩展和帕德近似的理论分析.
- 声波传播的数值模拟.
- 一级和二级同质化程序,包括威利斯合.
- 将同质化结果与数值数据进行比较.
主要成果:
- 获得有效性质的闭式表达式,包括不对称的威利斯合.
- 与第一阶方法相比,第二阶同质化程序产生了有效的散射系数,在相对较大的频率范围内有效.
- 研究了有效描述有效性的频率限制,并与布拉格带隙进行了比较.
结论:
- 第二阶同质化提供了在不对称周期管道中声波传播的更准确和更广泛的频率描述.
- 该研究促进了威利斯材料的理解和工程应用.
- 对有效性极限进行进一步的研究,特别是对于阻抗建模,是有必要的.
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