Finite element analysis on waves propagation in cylinders

The application of finite element method (FEM) in analyzing the waves propagation in cylinders is presented in this paper. The finite element equation is obtained by the virtual displacement theorem and solved by the central difference method. The spatial and temporal steps of discretization of the finite element computation are discussed. In order to compute high-frequency problems, a new sub-matrix method was set up and applied in the computations. The displacement fields, excited by a pulsed line-source with 5 MHz central frequency, are computed and displayed by gray plots. The waveforms of receiving points on the surface of the cylinders, identified as A-scan results, are also shown. The comparison between the FEM and experimental results shows that the FEM is a good way for analyzing the waves propagation in cylinders.