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Abstract
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In this study, vibration analysis of circular cylindrical shells with the two heads simply supported is done, using Donnel theory. First using the energy method and Hamilton principle, the govern-ing equations are derived. Moreever, a finite element model of cylindrical shell is modeled. The Effect of centrifugal forces, Coriolis acceleration, and the initial circular tension are included in the governing equations. The governing equations are solved using Galerkin’s method. Eventually the effect geometric parameters on the natural frequency and critical speed are investigated for both fixed and variable thickness shells. The analytical results are compared with the numerical results achieved by finite element software and they are verified. Results show that In cylindrical with variable thickness, the difference between the values of dimensionless natural frequencies in both Backward and Forward waves is significantly largest when longitudinal half-wave num-ber (m) increases. Also the effect of m on the dimensionless critical speeds in the Backward waves is more important than those of Forward waves case.
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