A Mode-Resolved Continuum Mechanics Model of Acoustic Wave Scattering From Embedded Cylinders
A Mode-Resolved Continuum Mechanics Model of Acoustic Wave Scattering From Embedded Cylinders
复制标题
嵌入式圆柱体声波散射的模式解析连续体力学模型
DOI：
10.1115/1.4040976
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Feser, Joseph P.
中科院分区：
文献类型：
--
作者：
Unni, Vineet;Feser, Joseph P.
在本文中，我们使用连续介质力学开发的弹性波散射从一个嵌入式圆柱体的分析处理，并表明，一个经典的论文对这个问题包含重要的错误，斜入射角，我们纠正。我们还开发失踪方程的散射截面在倾斜的角度和研究的弹性动力学对比机制的函数的散射截面的灵敏度。我们发现，在米氏散射制度的斜入射角，弹性和密度对比度是重要的机制，散射可以控制，但它们的效果可以相互抵消，类似于在平坦界面的反射理论。相比之下，我们发现，在瑞利散射制度，弹性和密度对比度总是互补的散射截面增加，但足够高的密度对比度，入射压缩和y-横模的散射截面几乎是独立的弹性对比度。开发的解决方案捕获所有可能的入射弹性波的方向，偏振和波长，包括从瑞利过渡到几何散射制度的散射物理，只要连续近似成立。该方法可以，例如，能够从微观原理计算热导率张量，这需要跨越所有可能的入射弹性波取向和热激发波长下的偏振的散射截面的知识。
In this paper, we use continuum mechanics to develop an analytic treatment of elastic wave scattering from an embedded cylinder and show that a classic treatise on the subject contains important errors for oblique angles of incidence, which we correct. We also develop missing equations for the scattering cross section at oblique angles and study the sensitivity of the scattering cross section as a function of elastodynamic contrast mechanisms. We find that in the Mie scattering regime for oblique angles of incidence, both elastic and density contrast are important mechanisms by which scattering can be controlled, but that their effects can offset one another, similar to the theory of reflection at flat interfaces. In comparison, we find that in the Rayleigh scattering regime, elastic and density contrast are always complimentary toward increasing scattering cross section, but for sufficiently high density contrast, the scattering cross section for incident compressional andy-transverse modes is nearly independent of elastic contrast. The solution developed captures the scattering physics for all possible incident elastic wave orientations, polarizations, and wavelengths including the transition from Rayleigh to geometric scattering regimes, so long as the continuum approximation holds. The method could, for example, enable calculation of the thermal conductivity tensor from microscopic principles which requires knowledge of the scattering cross section spanning all possible incident elastic wave orientations and polarizations at thermally excited wavelengths.
使用完美匹配的层边界解决频域中的原子声子结构散射问题的框架
影响因子：
3.2
作者：
R. Kakodkar;J. Feser
通讯作者：
J. Feser