title: Low frequency axisymmetric longitudinal guided waves in eccentric annular cylinders.
abstract: This paper studies the effect of axially uniform eccentricity on the modal structures and velocities of the lower order axisymmetric guided wave mode L(0,2) in circular tubes or pipes. The semi-analytical finite element method is mainly used, supported by fully three-dimensional finite element models and validated using experiments. The studies show that even a small eccentricity in the pipe can cause a loss in the L(0,2) mode axisymmetry, leading to its confinement in the thinned side of the pipe cross-section and also a reduction in mode velocities. The physics of this phenomenon is related to the feature-guiding and mode confinement effects noted in recent years in the literature, particularly studies on waveguides with local cross-section variations and curvature.
authors.affiliation: Centre for Nondestructive Evaluation, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India.
authors.forename: Roson Kumar
authors.initials: RK
authors.lastname: Pattanayak
authors.affiliation: Centre for Nondestructive Evaluation, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India.
authors.forename: Prabhakaran
authors.initials: P
authors.lastname: Manogharan
authors.affiliation: Centre for Nondestructive Evaluation, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India.
authors.forename: Krishnan
authors.initials: K
authors.lastname: Balasubramaniam
authors.affiliation: Centre for Nondestructive Evaluation, Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036, Tamil Nadu, India.
authors.forename: Prabhu
authors.initials: P
authors.lastname: Rajagopal