Control of Rayleigh wave propagation through imposing Mindlin boundary conditions on the surface
Control of Rayleigh wave propagation through imposing Mindlin boundary conditions on the surface
复制标题
DOI：
10.1016/j.jsv.2022.116931
复制
发表时间：
2022-04
影响因子：
4.7
通讯作者：
L. Pillarisetti;C. Lissenden;P. Shokouhi
中科院分区：
文献类型：
--
作者：
L. Pillarisetti;C. Lissenden;P. Shokouhi
为了控制平板中的低频兰姆波，最近建立了一种基于边界条件(BC)操纵的共振亚表面设计。这项研究确定了禁止瑞利波传播的必要边界条件，以便为优化的边界条件控制亚表面找到合理的设计方法。Mindlin BCS是柯西BCS的一种，它的分析研究显示了它在面波控制中的应用前景。在瑞利波传播路径上施加Mindlin边界元的频域和时间域有限元研究与分析预测一致，没有显示瑞利波的传播。模拟结果显示了瑞利波到体波的模式转换以及低幅度瑞雷波的反射。对于有限大小的BC贴片，模变换体波径向光束的扩展在表面附近保留了一些能量，这些能量可以在BC贴片的末端转换回瑞利波。因此，BC贴片必须足够长，才能有效地抑制表面波。最后，我们证明了Mindlin BCS可以由杆状棱镜谐振器施加在谐振器的纵频上。这些发现为促进表面波控制的耦合提供了新的见解，可能导致新的变形表面设计。
A resonant metasurface design based on boundary condition (BC) manipulation was recently established to control low-frequency Lamb waves in a plate. This study identifies the necessary BCs that forbid Rayleigh wave propagation in order to find a rational design methodology for an optimized BC-controlled meta-surface. An analytical study of Mindlin BCs, a type of Cauchy BCs, shows promise in surface wave control. The frequency-domain and time-domain finite element studies performed by imposing Mindlin BCs in the path of Rayleigh wave propagation are consistent with analytical predictions, exhibiting no Rayleigh wave transmission. The simulations reveal mode conversions from Rayleigh wave to bulk waves directed into the half-space and a low amplitude Rayleigh wave reflection. For a finite-sized BC patch, the radial beam spreading of the mode-converted bulk waves keeps some energy near the surface, which could convert back to Rayleigh waves at the end of the BC patch. Thus, the BC patch must be sufficiently long to effectively suppress surface waves. Finally, we show that the Mindlin BCs can be imposed by a rod-like prismatic resonator at the resonator’s longitudinal frequency. These findings provide new insights into the coupling that promotes surface wave control, potentially leading to novel metasurface designs.