Divergence instability of reinforced composite circular cylindrical shells

The present paper deals with a new analytical approach of nonlinear global buckling of spiral corrugated functionally graded carbon nanotube reinforced composite (FG-CNTRC) cylindrical shells subjected to radial loads. The equilibrium equation system is formulated by using the Donnell shell theory with the von Karman’s nonlinearity and an improved homogenization model for spiral corrugated structure. The obtained governing equations can be used to research the nonlinear postbuckling of mentioned above structures. By using the Galerkin method and a three term solution of deflection, an approximated analytical solution for the nonlinear stability problem of cylindrical shells is performed. The linear critical buckling loads and postbuckling strength of shells under radial loads are numerically investigated. Effectiveness of spiral corrugation in enhancing the global stability of spiral corrugated FG-CNTRC cylindrical shells is investigated.

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Buckling of Circular Cylindrical Shells Using a Displacement Function

Journal of Engineering for Industry ◽

10.1115/1.3438513 ◽

1974 ◽

Vol 96 (4) ◽

pp. 1322-1327

Author(s):

Shun Cheng ◽

C. K. Chang

Keyword(s):

Boundary Conditions ◽

Axial Compression ◽

Cylindrical Shells ◽

External Pressure ◽

Displacement Function ◽

Combined Loading ◽

Trial Solution ◽

Governing Differential Equation ◽

Circular Cylindrical Shells ◽

The Stability

The buckling problem of circular cylindrical shells under axial compression, external pressure, and torsion is investigated using a displacement function φ. A governing differential equation for the stability of thin cylindrical shells under combined loading of axial compression, external pressure, and torsion is derived. A method for the solutions of this equation is also presented. The advantage in using the present equation over the customary three differential equations for displacements is that only one trial solution is needed in solving the buckling problems as shown in the paper. Four possible combinations of boundary conditions for a simply supported edge are treated. The case of a cylinder under axial compression is carried out in detail. For two types of simple supported boundary conditions, SS1 and SS2, the minimum critical axial buckling stress is found to be 43.5 percent of the well-known classical value Eh/R3(1−ν2) against the 50 percent of the classical value presently known.

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Vibration of rotating circular cylindrical shells with distributed springs

Journal of Mechanics ◽

10.1093/jom/ufab008 ◽

2021 ◽

Vol 37 ◽

pp. 346-358

Author(s):

Fuchun Yang ◽

Xiaofeng Jiang ◽

Fuxin Du

Keyword(s):

Boundary Conditions ◽

Galerkin Method ◽

Shell Theory ◽

Rotation Speed ◽

Cylindrical Shells ◽

Free Vibrations ◽

Governing Equations ◽

Natural Response ◽

Circular Cylindrical Shells ◽

The Galerkin Method

Abstract Free vibrations of rotating cylindrical shells with distributed springs were studied. Based on the Flügge shell theory, the governing equations of rotating cylindrical shells with distributed springs were derived under typical boundary conditions. Multicomponent modal functions were used to satisfy the distributed springs around the circumference. The natural responses were analyzed using the Galerkin method. The effects of parameters, rotation speed, stiffness, and ratios of thickness/radius and length/radius, on natural response were also examined.

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