GUIDED WAVE BEHAVIOR ANALYSIS IN MULTI-LAYERED INHOMOGENEOUS
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homogeneous anisotropic plates. It has been reported before that guided waves in inhomogeneous plates tend to follow preferred directions based on the location of ply-groups as well as the orientation of the fibers [1]. The pattern obtained by imaging the leaked energy into the surrounding fluid (earlier called as Plate Wave Flow Patterns) has been shown to indicate fiber orientations [2]. In this paper, a model based on the Thomson-Haskell transfer matrix is employed to obtain the internal distributions of the energy vector within the inhomogeneous plate. Based on the theoretical results, the plate wave flow patterns can be predicted and compared with the experimental results. The results provide insight into the understanding of the generation mechanism of guided wave mode patterns in inhomogeneous plates. THEORETICAL BACKGROUND Consider a general anisotropic multilayered plate immersed in water. The plate consists of an arbitrary number of general anisotropic layers n, rigidly bonded at their interfaces as shown in Figure 1. Without losing generality, it is assumed that leaky plate waves propagate along the Xl direction. First consider the plane wave propagation in a general anisotropic multi-layered structure as shown in Figure 1. The displacements of the wave are given by
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