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Asymmetric vibration of viscoelasticallydamped multilayered conical shell

Published online by Cambridge University Press:  04 July 2016

K. N. Khatri*
Affiliation:
Armament Research and Development EstablishmentDefence R&D OrganisationPoona, India

Abstract

Asymmetric vibration of multilayered conical shell withcore layers of viscoelastic material areinvestigated in this paper. The analysis presentedherein considers bending, extension in plane shearand transverse shear deformations in each of thelayers, and also includes rotary, longitudinaltranslatory and transverse inertias. Appropriatetrigonometric series are used as solution functionsin the Galerkin method to reduce the governingequations to a set of matrix equations. Thecorresponding principle of linear viscoelasticityfor harmonic motion is used for evaluating thedamping effectiveness of shells with elastic andviscoelastic layers. A computer program has beendeveloped for determining the resonance frequenciesand associated system loss factors for various modesof families of asymmetric vibration of a generalmultilayered conical shell consisting of anarbitrary number of specially orthotropic materiallayers. Variation of resonance frequencies and theassociated system loss factors with total thicknessparameter and circumferential modal number forthree, five and seven layered conical shells, withthree sets of classical end conditions: simplysupported at both ends, clamped-clamped andfree-free, which can be of some use to designers,are been reported.

Information

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1996 

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