Ultrasonic non-specular reflection and transmission for an immersed multilayered composite

The implementation of an ultrasonic method of evaluation of composite plates requires a good knowledge of the interaction of ultrasonic beam emitted by the transducers, with such a plate immersed in a fluid. The model of ultrasonic propagation in anisotropic multilayered materials developed here makes the study of this interaction possible. The interaction of ultrasonic beams with fluid-loaded multilayered anisotropic structures is treated numerically by combining the propagator matrix and the angular spectrum decomposition technique. The numerical model developed during the course of investigation is used to calculate the reflection and transmission profiles for a Gaussian beam incident on a multilayered composite. The model allows the calculations of the reflected and transmitted ultrasonic fields for a multilayered composite, absorbing or not. The emphasis is placed on the regime of nonspecular reflection that is characterized by the strong coupling between the specularly reflected beam and the leaky waves supported by the structure corresponding to the incidence in the vicinity of multilayered Rayleigh modes.