Wave dispersion in thin-walled orthotropic waveguides using the first order shear deformation theory. (June 2016)

• Record Type: Journal Article
• Authors: Mazzotti, M.; Bartoli, I.; Miniaci, M.; Marzani, A.
• Is Part Of: Thin-walled structures. Volume 103(2016)
• Page Start: 128
• Page End: 140
• Publication Date: 2016-06
• Subjects: Thin-walled waveguides -- SAFE -- Dispersion -- Energy velocity -- Axial prestress -- Attenuation; Thin-walled structures -- Periodicals; 690.1
• DOI: 10.1016/j.tws.2016.02.014
• Languages: English
• ISSNs: 0263-8231

Abstract

Abstract: The aim of this paper is to extract the dispersion parameters, i.e. phase velocity, energy velocity and attenuation, of orthotropic thin-walled waveguides with generic cross-section. To this end, a semi-analytical finite element (SAFE) formulation is presented, which is based on the Reissner–Mindlin theory of curved shells. Complex axial wavenumbers and mode shapes of guided wave modes are extracted from a second-order polynomial eigenvalue problem, while the energy velocity is post-processed using the computed eigensolutions and SAFE operators. Different numerical examples are proposed, for which the obtained results are in very good agreement with those computed using other well-stated SAFE formulations. Abstract : Highlights: A SAFE formulation based on the Reissner–Mindlin theory of shells is proposed. Thin-walled waveguides with generic curved cross-section are considered. Material orthotropy and viscoelasticity are taken into account. A closed formula for the energy velocity based on SAFE operators is presented. It is shown that an axial prestress leads to a decrease of the attenuation values.