| dc.description.abstract | Understanding the dynamic characteristics of ultrasonic guided wave in structures is important,
as it is one of the methods that are widely used in many different areas of industrial sectors and
inspections, such as Non-Destructive Testing (QNDT). The ultrasonic guided wave is
transmitted and reflected at the surface of the wave materials. A detailed study and interpretation
of mode conversion in guided wave is required.
The current research presents a theoretical study of guided wave in piezoelectric cylinders based
on the theory of elasticity. Two different methods were employed to study dispersion relations in
piezoelectric cylinders. One of them is a finite element method and the other is an analytical
method. In the analytical method, three displacement potentials are introduced to obtain
dispersion relation of guided wave modes. This method is developed primarily to cross check
finite element results.
In the finite element method, the dispersion equation has been formulated as a generalized
eigenvalue problem by treating mechanical displacements and electric potential with one
dimensional (quadratic) finite element model through the thickness of the cylinder. Computer
codes have been developed and verified by comparing with limited published results. The
numerical results are presented for different cylinders and electric boundary conditions. In the
numerical studies, three dimensional wave spectrum surfaces were generated. Discussion of
guided wave propagating in different direction in cylinders was given as well. | |
