Curvature effects on wave propagation in an infinite pipe

Abstract

Advanced research into non-destructive control of industrial pipeworks provides several acoustical methods for inspection of their structural integrity. Applying guided waves is one possible solution to detect and identify different flaws. Many studies have shown the importance of complex waves describing the interaction phenomena at the vicinity of the defects, modeled as geometrical discontinuities. Therefore it is important to understand the behavior of this type of waves in order to describe correctly wave interaction with the discontinuities like joints, cracks and solid deposits. This paper presents theoretical study of axi-symmetric longitudinal guided and complex wave propagation and in elastic pipes. The asymptotic dispersion equation of the pipe gives a comprehensive representation of all wave types presented in the structure: propagating, non-propagating and inhomogeneous waves. Dispersion curves corresponding to real, imaginary wave number for the longitudinal modes in a wide frequency-thickness range and different radii of the pipe are given.