Transient torsional wave propagation in finite and infinite multilayered pipes

Abstract

Multilayered pipes are widely used in many engineering settings. Using guided wave is one of the most efficient techniques to inspect them. To inspect multilayered pipes using guided waves, it is of paramount importance to investigate the excitation and propagation of the guided wave within them. In this study, the solution of the elastodynamic response of the finite and infinite multilayered pipes to axisymmetric torsional body and surface forces is derived by the eigenfunction expansion method (EEM), based on which the excitation and propagation of each torsional mode can be quantitatively investigated. As an example of the application of the theory presented here, the transient torsional waves propagating in an Al-Cu bi-layered pipe is numerically studied. The numerically evaluated analytic solution agrees very well with that obtained using the finite element method (FEM).