Guided elastic waves in infinite free-clamped hollow cylinders

Guided elastic-wave-inspection technique for hollow cylinders has received plenty of attention in recent years because of its high efficiency and low cost. To apply guided elastic waves to defects detection, it is necessary to investigate the propagation of guided waves in the hollow cylinders under all kinds of boundary conditions. In this paper, the dispersion equations of torsional, longitudinal and flexural guided waves in the hollow cylinders with traction-free and clamped lateral boundaries are derived by elastodynamic theory, based on which the phase and group velocity dispersion curves of the guided waves mentioned above are obtained. And the dispersion properties of these waves are discussed in detail. The transient wave in a free-clamped hollow cylinder is simulated by the finite element method (FEM). The time–frequency distribution of the transient wave agrees well with the theoretical group velocity dispersion curves.