Dynamic Buckling of a Cylindrical Shell with Variable Thickness Subject to a Time-Dependent External Pressure Varying as a Power Function of Time (original) (raw)
Related papers
Nonlinear behavior and buckling of cylindrical shells subjected to localized external pressure
Journal of Engineering Mathematics, 2013
Buckling loads and postbuckling behavior of cylindrical shells subjected to localized external pressure are considered. The modified extended Kantorovich method with path-tracing technique is applied to determine the buckling loads of the cylindrical shells. It is found that the load is dependent nonmonotonically on geometrical parameters of the area subjected to external pressure. Respective postbuckling shapes show correlation with the shapes corresponding to secondary bifurcation paths for the cases of a cylindrical shell under uniform external pressure and a cylindrical shell under uniform axial load.
On dynamic buckling phenomena in axially loaded elastic-plastic cylindrical shells
International Journal of Non-Linear Mechanics, 2002
Some characteristic features of the dynamic inelastic buckling behaviour of cylindrical shells subjected to axial impact loads are discussed. It is shown that the material properties and their approximations in the plastic range in uence the initial instability pattern and the ÿnal buckling shape of a shell having a given geometry. The phenomena of dynamic plastic buckling (when the entire length of a cylindrical shell wrinkles before the development of large radial displacements) and dynamic progressive buckling (when the folds in a cylindrical shell form sequentially) are analysed from the viewpoint of stress wave propagation resulting from an axial impact. It is shown that a high velocity impact causes an instantaneously applied load, with a maximum value at t = 0 and whether or not this load causes an inelastic collapse depends on the magnitude of the initial kinetic energy. ?
Buckling of Thin Cylindrical Shell Subject to Uniform External Pressure
The buckling of cylindrical shells under uniform external pressure loading has been widely investigated. In general, when tubes are subjected to external pressure, collapse is initiated by yielding, but interaction with instability is significant, in that imperfections associated with fabrication of shells reduce the load bearing capacity by a significant amount even when thickness is considerable. A specific buckling analysis is used to predict collapse failure of long pressure vessels and pipelines when they are subjected to external over-pressure. The problem of buckling for variable load conditions is relevant for the optimisation of several Nuclear Power Plant applications as, for instance, the IRIS (International Reactor Innovative and Secure) LWR integrated Steam Generator (SG) tubes. In this paper, we consider in addition to the usual assumptions of thin shell, homogeneous and isotropic material, also the tube geometric imperfections and plastic deformations that may affect ...
AIAA Journal, 1995
A formulation based on the three-dimensional theory of elasticity Is employed to study the buckling of an onhotropic cylindrical sbell under combined external pressure and axial compression. A properly defined load iDt.eraction panuueur expresses the ratio of axial compression and exurnal pressure loading, and critical loads an thus derived for a given load Inuraction. The results from this elasticity solution an compand with the aiticalloads predicted by the orthotropic Donnell and Timoshenko nonshallow classical shell formulations. Two cases of ortbotroplc material are colISldered with stiffness colIStants typical of glass/epoxy and grapblte/epoxy. Furthenuore. two cases of load Inuraction are considered, representing a relatively blgh and a relatively low axial load. For both load Interaction cases considered and for both materials, the Donnell and the Timoshenko bifurcation points are bigher than the elasticity SOlution, which means that both shell theories are nonconservative. However, the bifurcation points from the Tlmoshenko formulation are always found to be closer to the elasticity predictions than the ones from the Donnell formulation. An additional common observation Is that, for a higb value of the load inuraction parameter (relatively high axial load), the Tlmoshenko shell theory Is performing remarkahly-ell, approaching closely the elasticity SOlution, especially for thick cOlIStroction. Finally, a comparison with some ..-ailable results from higher order shell tbeories for pure external pressure Indicates that these improved shell theories seem to be adequate for the example cases that were studied.
On load interaction in the non linear buckling analysis of cylindrical shells
Advances in Engineering Software, 1991
The elastic stability of shells or shell-like structures under two independent load parameters is considered. One of the loads is associated to a limit point form of buckling, whereas the second is a bifurcation. A simple one degree of freedom mechanical system is first investigated, for which an analytical solution is possible. Next, a cylindrical shell under the combined action of axial load and localised lateral pressure is studied via a non linear, two-dimensional, finite ele ment discretization. It is shown that both problems display the same general behaviour, with a stability boundary in the load space which is convex towards the region of stability. The results show the need of performing a full non-linear analysis to evaluate the stability boundary for the class of interaction prob lems considered.
International Journal of Solids and Structures, 2001
A new concept is presented for the dynamic elastic±plastic axisymmetric buckling of circular cylindrical shells under axial impact. The phenomena of dynamic plastic buckling (when the entire length of the shell wrinkles before the development of large radial displacements) and dynamic progressive buckling (when the shell folds form sequentially) are analysed from the viewpoint of stress wave propagation resulting from an axial impact. The conditions for the development of dynamic plastic buckling are obtained.
Buckling of a thin cylindrical sandwich shell composed of elastic isotropic layers with different elastic properties under normal external pressure is the subject of this investigation. Differential equations based on the assumptions of the generalized kinematic hypothesis for the whole sandwich are used as the governing ones. Two variants of the joint support conditions are considered at the shell edges: a) there are the infinite rigidity diaphragms inhibiting relative shears of layers along the shell edges, b) the diaphragms are absent. Using the asymptotic approach, the critical pressure and buckling modes are constructed in the form of the superposition of functions corresponding to the main stress-strain state and the edges integrals. As an example, a three-layered cylinder with the magnetorheological elastomer (MRE) embedded between elastic layers under different levels of magnetic field is studied. Physical properties of the magnetorheological (MR) layer are assumed to be fun...
In this paper, the effects of initial imperfections on the buckling behavior of thick cylindrical shells and curved panels are investigated. It is assumed that the shell has an axisymmetric and periodic initial imperfection in the axial direction. The shell is assumed to have different boundary conditions and subjected to pure external pressure loading. Governing differential equations are developed on the basis of the second Piola-Kirchhoff stress tensor and are reduced to a homogenous linear system of equations using the differential quadrature method. The effects of different boundary conditions, geometric ratios, curvature and imperfection parameter on the buckling behavior of isotropic thick cylindrical shells and curved panels are carefully discussed. The results obtained by the present method are verified with finite element solutions and those reported in the literature.
Thin-Walled Structures, 1991
Buckling and postbuckling behaviour of perfect and imperfect cylindrical shells of finite length subject to combined loading of external pressure and axial compression are considered. Based on the boundary layer theory which includes the edge effect in the buckling of shells, a theoretical analysis for the buckling and postbuckling of circular cylindrical shells under combined loading is presented using a singular perturbation technique. Some interaction curves for perfect and imperfect cylindrical shells are given. The analytical results obtained are compared with some experimental data in detail, and it is shown that both agree well. The effects of initial imperfection on the interactive buckrng load and postbuckling behaviour of cylindrical shells have also been discussed NOTATION
Mathematical Problems in Engineering, 2009
The static buckling of a cylindrical shell of a four-lobed cross section of variable thickness subjected to non-uniform circumferentially compressive loads is investigated based on the thin-shell theory. Modal displacements of the shell can be described by trigonometric functions, and Fourier's approach is used to separate the variables. The governing equations of the shell are reduced to eight first-order differential equations with variable coefficients in the circumferential coordinate, and by using the transfer matrix of the shell, these equations can be written in a matrix differential equation. The transfer matrix is derived from the nonlinear differential equations of the cylindrical shells by introducing the trigonometric series in the longitudinal direction and applying a numerical integration in the circumferential direction. The transfer matrix approach is used to get the critical buckling loads and the buckling deformations for symmetrical and antisymmetrical shells....