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Asymmetric vibration of viscoelastically damped multilayered conical shell

Published online by Cambridge University Press:  04 July 2016

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

Asymmetric vibration of multilayered conical shell with core layers of viscoelastic material are investigated in this paper. The analysis presented herein considers bending, extension in plane shear and transverse shear deformations in each of the layers, and also includes rotary, longitudinal translatory and transverse inertias. Appropriate trigonometric series are used as solution functions in the Galerkin method to reduce the governing equations to a set of matrix equations. The corresponding principle of linear viscoelasticity for harmonic motion is used for evaluating the damping effectiveness of shells with elastic and viscoelastic layers. A computer program has been developed for determining the resonance frequencies and associated system loss factors for various modes of families of asymmetric vibration of a general multilayered conical shell consisting of an arbitrary number of specially orthotropic material layers. Variation of resonance frequencies and the associated system loss factors with total thickness parameter and circumferential modal number for three, five and seven layered conical shells, with three sets of classical end conditions: simply supported at both ends, clamped-clamped and free-free, which can be of some use to designers, are been reported.

Type
Research Article
Information
The Aeronautical Journal , Volume 100 , Issue 997 , September 1996 , pp. 285 - 294
Copyright
Copyright © Royal Aeronautical Society 1996 

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