Belloncle Gaël, Luppé Francine, Franklin Hervé, Conoir Jean-Marc
LAUE, UMR CNRS 6068, Place Robert Schuman, 76610 Le Havre, France.
Ultrasonics. 2004 Apr;42(1-9):511-4. doi: 10.1016/j.ultras.2004.01.098.
A numerical study of the guided modes in a water-saturated poroelastic plate that obeys the Biot theory is presented. In the first part, we study the leaky guided modes and the angular resonances when the slow wave does not propagate. Two types of guided modes exist. The first ones occur from coupling of the fast longitudinal wave with the shear wave; most of them propagate whatever the frequency is, provided that it is not close to their cut-off frequencies. The leaky guided modes of the second type occur from coupling of the two longitudinal waves and the shear wave. These modes do not propagate (they are highly damped) as long as the slow wave remains diffusive. We show that the characteristics of the angular resonances can be linked to the leaky guided waves of the first type in the same way as for an elastic plate. The guided modes of the second type may not be associated to angular resonances. In the second part, we consider a thinner plate in a higher frequency range so that the slow wave can propagate. Once again its influence is studied both on the leaky guided modes and on the angular resonances.
本文给出了对服从比奥理论的水饱和多孔弹性板中导模的数值研究。在第一部分，我们研究慢波不传播时的泄漏导模和角共振。存在两种类型的导模。第一种是由快纵波与剪切波耦合产生的；只要频率不接近其截止频率，它们中的大多数无论频率如何都能传播。第二种泄漏导模是由两个纵波和剪切波耦合产生的。只要慢波保持扩散状态，这些模式就不会传播（它们是高阻尼的）。我们表明，角共振的特性可以与弹性板一样以相同的方式与第一种类型的泄漏导波相关联。第二种类型的导模可能与角共振无关。在第二部分，我们考虑在更高频率范围内的更薄板，以便慢波能够传播。再次研究了它对泄漏导模和角共振的影响。
