在使用膨胀室的不对称和对称声学系统中分析缺陷模式特征
Ilyas Antraoui1, Ali Khettabi1, Mohammed Sallah2
1Laboratory of Materials, Waves, Energy and Environment, Department of Physics, Faculty of Sciences, Mohammed First University, Oujda, 60000, Morocco.
Scientific reports
|January 20, 2025
概括
这项研究研究了有缺陷的周期膨胀室中的声波分散. 研究人员发现,缺陷在带间隙内引入独特的声学峰值,对称结构显示两个峰值,不对称结构显示一个,受缺陷几何学的影响.
科学领域:
- 声学 声学 在声学上
- 波浪物理 波浪物理
- 材料科学 材料科学 材料科学
背景情况:
- 周期结构具有独特的波传播特性,包括频段间隙.
- 引入周期系统中的缺陷可以将波局部化,并在这些频段间隙内创建局部化模式.
- 了解有缺陷的周期结构中的声波行为对于设计先进的声学设备至关重要.
研究的目的:
- 为了研究声波在具有缺陷的有限周期膨胀腔系统中的分散.
- 分析由于结构缺陷而在禁止的频段内出现的局部模式 (一致峰值) 的特性.
- 为了比较对称和不对称的有缺陷的周期结构的声响应.
主要方法:
- 使用转移矩阵方法来建模和分析声波传播.
- 计算分散关系并确定在正常发病率下一致的峰值的特征.
- 检查两种类型的结构:具有缺陷的对称和不对称周期膨胀腔.
主要成果:
- 一致的峰值,代表局部声学模式,出现在有缺陷的周期结构的声带间隙内.
- 不对称结构的缺陷导致带间隙内单个一致的峰值.
- 对称结构的缺陷导致带间隙内有两个一致的峰值.
- 在不对称的结构中,一致的峰值的高度对缺陷导向器的截面变化很敏感.
- 缺陷指南的长度会影响在带间隙内观察到的一致峰值的数量.
结论:
- 周期膨胀室的缺陷在频段间隙内产生局部声学模式,为波浪操纵提供了可能性.
- 缺陷的对称性及其几何参数 (截面,长度) 显著影响这些局部模式的数量和特征.
- 这些发现为设计新型声学过器和其他基于波的设备提供了宝贵的见解.
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