Semi analytical study of stress and deformation analysis of anisotropic shells of revolution including first order transverse shear deformation

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2008

Author

Oygür, Özgür Sinan

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In this study, anisotropic shells of revolution subject to symmetric and unsymmetrical static loads are analysed. In derivation of governing equations to be used in the solution, first order transverse shear effects are included in the formulation. The governing equations can be listed as kinematic equations, constitutive equations, and equations of motion. The equations of motion are derived from Hamilton’s principle, the constitutive equations are developed under the assumptions of the classical lamination theory and the kinematic equations are based on the Reissner-Naghdi linear shell theory. In the solution method, these governing equations are manipulated and written as a set called fundamental set of equations. In order to handle anisotropy and first order transverse shear deformations, the fundamental set of equations is transformed into 20 first order ordinary differential equations using finite exponential Fourier decomposition and then solved with multisegment method of integration, after reduction of the two-point boundary value problem to a series of initial value problems. The results are compared with finite element analysis results for a number of sample cases and good agreement is found. Case studies are performed for circular cylindrical shell and truncated spherical shell geometries. While reviewing the results, effects of temperature and pressure loads, both constant and variable throughout the shell, are discussed. Some drawbacks of the first order transverse shear deformation theory are exhibited.

Subject Keywords

Aerospace engineering., Aeronautical Engineering.

URI

http://etd.lib.metu.edu.tr/upload/2/12609870/index.pdf
https://hdl.handle.net/11511/18219

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

Ö. S. Oygür, “Semi analytical study of stress and deformation analysis of anisotropic shells of revolution including first order transverse shear deformation,” M.S. - Master of Science, Middle East Technical University, 2008.