方形局部共振音声晶体中的几何缺陷分析:对建模方法的比较研究esa)
L Katch1, M Moghaddaszadeh2, C L Willey3
1Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
The Journal of the Acoustical Society of America
|November 14, 2023
概括
通过分析其改变的动态响应,可以检测声波晶体中的缺陷. 这项研究引入了计算价格低廉的模型,以预测音声晶体行为和带隙中缺陷诱导的变化.
科学领域:
- 材料科学 材料科学 材料科学
- 声学 声学 在声学方面
- 固体力学 固体力学是什么
背景情况:
- 声波晶体表现出独特的带隙特性,对于波浪操纵至关重要.
- 制造缺陷可以显著改变音声晶体的动态反应和带隙行为.
- 有效的缺陷检测方法对于声波晶体应用中的质量控制至关重要.
研究的目的:
- 为了研究一个方形音声晶体单元细胞中由特定缺陷 (释放和缩短的腿) 引起的动态特征.
- 开发和验证用于预测音声晶体缺陷行为的计算价格低廉的模型.
- 为了评估缺陷对无限和有限的音声晶体阵列的影响.
主要方法:
- 波有限元法 (WFEM) 用于分析音声晶体动力学.
- 估计连续块模型 (ACL) 作为一个计算效率高的替代方案.
- 对WFEM和ACL与完整的有限元模型 (FEM) 进行验证.
- 对分散曲线和频率响应函数 (FRF) 的分析.
主要成果:
- 鉴定出了由缺陷引起的模式,这些模式分裂了原始语音晶体的局部共振带隙.
- 由于缩短了单元细胞腿,观察到新的反共振频率.
- 无论是WFEM和ACL模型,都成功地预测了有缺陷的无限和有限的语音晶体数组的行为.
- 该研究验证了近似模型的准确性与完整的FEM相比.
结论:
- 在计算上便宜的模型 (WFEM和ACL) 可以准确地预测声波晶体中缺陷诱导的动态特征.
- 了解缺陷行为是利用改变频率响应用于缺陷检查的关键.
- 开发的方法适用于评估复杂的音声晶体几何学的缺陷.
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