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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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References

1. Nakra, B.C. Vibration control with viscoelastic materials III, Shock Vib Digest, 1984, 16, pp 17–22.Google Scholar
2. Bert, C.W. and Eole, D.M. Dynamics of composite sandwich and stiffened shell structures, J Spacecra Rocket, 1969, 6, pp 1345–1361.Google Scholar
3. Leissa, A.W. Vibration of shells, NASA SP, 1973, 288.Google Scholar
4. Siu, C.C. and Bert, C.W. Free vibrational analysis of sandwich conical shells with free edges, J Acoust Soc Am, 1970, 47, pp 943–945. Google Scholar
5. Wilkins, D.J., Bert, C.W. and Egle, D.M., Free vibrations of orthotropic sandwich conical shells with various boundary conditions, J Sound Vib, 1970, 13, pp 211–228.Google Scholar
6. Bacon, M.D. and Bert, C.W. Unsymmetric free vibration of or thotropic sandwich shells of revolution, AIAA J, 1967, 5, pp 413–417.Google Scholar
7. Bert, C.W. and Ray, J.D. Vibration of orthotropic sandwich conical shells with free edges, IntJMech Sci, 1969, 11, pp 767–779.Google Scholar
8. Chandrasekaran, K. and Ramamurti, V, , Asymmetric free vibra tion of layered conical shells, ASME, 1981, 81, DET - 68.Google Scholar
9. Khatri, K.N. Vibrations of arbitrarily laminated fiber reinforced composite material truncated conical shell, J Reinforced Plastics Composite, 1995, 14, pp 923–948.Google Scholar
10. Bland, D.R. The Theory of Linear Viscoelasticity, 1960.Google Scholar
11. Hashin, Z. Complex moduli of viscoelastic composites-I: General theory and application to particulate composites, Int J Solid Struc, 1970, 6, pp 539–552.Google Scholar
12. Rao, Y.V.K.S. and Nakra, B.C. Vibrations of unsymmetrical sand wich beams and plates with viscoelastic cores, J Sound Vib, 1974, 34, pp 309–326.Google Scholar
13. Ungar, E.E. and Kerwin, E.M. LOSS factors of viscoelastic systems in terms of energy concepts, J Acoust Soc Am, 1962, 34, pp 954–957.Google Scholar
14. Alam, N. and Asnani, N.T. Vibration and damping analysis of mul- tilayered rectangualr plates with constrained viscoelastic layers, J Sound Vib, 1984, 97, pp 597–614.Google Scholar
15. Weingarten, V.I. Free vibrations of ring stiffened conical shells, ASCE J Eng Mech Div, 1965, 91, pp 69–87.Google Scholar
16. Alam, N. and Asnani, N.T. Vibration and damping analysis of a multilayered cylindrical shell, Part II, AIAA J, 1984, 22, pp 975–981.Google Scholar
17. Platus, D.H. Conical shell vibrations, NASA TN D-2767, 1965.Google Scholar