Comments on “Automated Optimal Design of Frame Reinforced, Submersible, Circular, Cylindrical Shells” by M. Pappas and A. Allentuch

1974 ◽  
Vol 18 (02) ◽  
pp. 139-139
Author(s):  
H. Becker
Keyword(s):  
Cylindrical Shell ◽  
Optimal Design ◽  
Closed Form ◽  
Circular Cylindrical Shell ◽  
Minimum Weight ◽  
Cylindrical Shells ◽  
External Pressure ◽  
Circular Cylindrical Shells

Pappas and Allentuch in the title paper computerized the investigation of a minimum-weight, ring-stiffened, elastic circular cylindrical shell under external pressure and obtained results similar to those found by Gerard in closed form in 1961.

Free Asymmetric Vibrations of Composite Full Circular Cylindrical Shells Stiffened by a Bonded Central Shell Segment

2004 ◽  
Author(s):  
U. Yuceoglu ◽  
V. O¨zerciyes
Keyword(s):  
Cylindrical Shell ◽  
Shell Theory ◽  
Natural Frequencies ◽  
Circular Cylindrical Shell ◽  
Cylindrical Shells ◽  
Adhesive Layer ◽  
Shear Stresses ◽  
First Order ◽  
Stress Resultant ◽  
Circular Cylindrical Shells

This study is concerned with the “Free Asymmetric Vibrations of Composite Full Circular Cylindrical Shells Stiffened by a Bonded Central Shell Segment.” The base shell is made of an orthotropic “full” circular cylindrical shell reinforced and/or stiffened by an adhesively bonded dissimilar, orthotropic “full” circular cylindrical shell segment. The stiffening shell segment is located at the mid-center of the composite system. The theoretical analysis is based on the “Timoshenko-Mindlin-(and Reissner) Shell Theory” which is a “First Order Shear Deformation Shell Theory (FSDST).” Thus, in both “base (or lower) shell” and in the “upper shell” segment, the transverse shear deformations and the extensional, translational and the rotary moments of inertia are taken into account in the formulation. In the very thin and linearly elastic adhesive layer, the transverse normal and shear stresses are accounted for. The sets of the dynamic equations, stress-resultant-displacement equations for both shells and the in-between adhesive layer are combined and manipulated and are finally reduced into a ”Governing System of the First Order Ordinary Differential Equations” in the “state-vector” form. This system is integrated by the “Modified Transfer Matrix Method (with Chebyshev Polynomials).” Some asymmetric mode shapes and the corresponding natural frequencies showing the effect of the “hard” and the “soft” adhesive cases are presented. Also, the parametric study of the “overlap length” (or the bonded joint length) on the natural frequencies in several modes is considered and plotted.

Experimental Study on Pre-Stressed Circular Cylindrical Shell

2012 ◽  
Author(s):  
Antonio Zippo ◽  
Marco Barbieri ◽  
Matteo Strozzi ◽  
Vito Errede ◽  
Francesco Pellicano
Keyword(s):  
Experimental Study ◽  
Cylindrical Shell ◽  
Axial Load ◽  
Nonlinear Vibrations ◽  
Circular Cylindrical Shell ◽  
Cylindrical Shells ◽  
Experimental Studies ◽  
Element Model ◽  
Experimental Setup ◽  
Circular Cylindrical Shells

In this paper an experimental study on circular cylindrical shells subjected to axial compressive and periodic loads is presented. Even though many researchers have extensively studied nonlinear vibrations of cylindrical shells, experimental studies are rather limited in number. The experimental setup is explained and deeply described along with the analysis of preliminary results. The linear and the nonlinear dynamic behavior associated with a combined effect of compressive static and a periodic axial load have been investigated for different combinations of loads; moreover, a non stationary response of the structure has been observed close to one of the resonances. The linear shell behavior is also investigated by means of a finite element model, in order to enhance the comprehension of experimental results.

Bending of Cord Composite Laminate Cylindrical Shells

2003 ◽  
Vol 70 (3) ◽  
pp. 364-373 ◽  
Author(s):  
A. J. Paris ◽  
G. A. Costello
Keyword(s):  
Cylindrical Shell ◽  
Differential Equations ◽  
Closed Form ◽  
Composite Laminate ◽  
Circular Cylindrical Shell ◽  
Cylindrical Shells ◽  
Axisymmetric Loading ◽  
Shell Axis

A theory for the bending of cord composite laminate cylindrical shells is developed. The extension-twist coupling of the cords is taken into account. The general case of a circular cylindrical shell with cord plies at various angles to the shell axis is considered. The differential equations for the displacements are derived. These equations are solved analytically in closed form for a shell subjected to axisymmetric loading and no in-plane tractions. The results of the current study are compared with the commonly used Gough-Tangorra and Akasaka-Hirano solutions.

Creep Buckling Analyses of Circular Cylindrical Shells Under Axial Compression—Bifurcation Buckling Analysis by the Finite Element Method

1987 ◽  
Vol 109 (2) ◽  
pp. 179-183 ◽  
Author(s):  
N. Miyazaki
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Cylindrical Shell ◽  
Axial Compression ◽  
Circular Cylindrical Shell ◽  
Cylindrical Shells ◽  
The Finite Element Method ◽  
Bifurcation Buckling ◽  
Creep Buckling ◽  
Circular Cylindrical Shells

The finite element method is applied to the creep buckling of circular cylindrical shells under axial compression. Not only the axisymmetric mode but also the bifurcation mode of the creep buckling are considered in the analysis. The critical time for creep buckling is defined as either the time when a slope of a displacement versus time curve becomes infinite or the time when the bifurcation buckling occurs. The creep buckling analyses are carried out for an infinitely long and axially compressed circular cylindrical shell with an axisymmetric initial imperfection and for a finitely long and axially compressed circular cylindrical shell. The numerical results are compared with available analytical ones and experimental data.

Interaction Curves for Circular Cylindrical Shells According to the Mises or Tresca Yield Criterion

1962 ◽  
Vol 29 (2) ◽  
pp. 375-380 ◽  
Author(s):  
P. G. Hodge ◽  
Joseph Panarelli
Keyword(s):  
Cylindrical Shell ◽  
Circular Cylindrical Shell ◽  
Plastic Material ◽  
Yield Criterion ◽  
External Pressure ◽  
Shell Material ◽  
Perfectly Plastic ◽  
Axial Tensile ◽  
Circular Cylindrical Shells ◽  
Interaction Curves

A circular cylindrical shell is subjected to uniform internal or external pressure and a constant axial tensile or compressive stress. The interaction curve constituting load combinations which just cause plastic flow of a rigid/perfectly plastic material depends upon the assumed yield criterion of the shell material. Close bounds on the interaction curve are found when the material yields according to either the Tresca or Mises criterion.

scholarly journals Vibration Analysis of Grid-Stiffened Circular Cylindrical Shells with Full Free Edges

2011 ◽  
Vol 18 (4) ◽  
pp. 23-27 ◽  
Author(s):  
J. Jam ◽  
M. Zadeh ◽  
H. Taghavian ◽  
B. Eftari
Keyword(s):  
Cylindrical Shell ◽  
Vibration Analysis ◽  
Circular Cylindrical Shell ◽  
Cylindrical Shells ◽  
Equivalent Stiffness ◽  
Finite Element Approach ◽  
Stiffness Model ◽  
Element Approach ◽  
Circular Cylindrical Shells ◽  
Free Edges

Vibration Analysis of Grid-Stiffened Circular Cylindrical Shells with Full Free Edges Free vibration of grid stiffened circular cylindrical shells is investigated based on the first Love's approximation theory using Galerkin method. Full free edges are considered for boundary conditions. An equivalent stiffness model (ESM) is used to develop the analytical solution of the grid stiffened circular cylindrical shell. The effect of helical stiffeners orientation and some of the geometric parameters of the structure have been shown. The accuracy of the analysis has been examined by comparing results with those available in the literature and finite element approach.

Relationship between Bending Solutions of FGM and Homogenous Circular Cylindrical Shells

2013 ◽  
Vol 353-356 ◽  
pp. 3236-3242
Author(s):  
Ze Qing Wan ◽  
Shi Rong Li
Keyword(s):  
Cylindrical Shell ◽  
Numerical Solutions ◽  
Volume Fraction ◽  
Circular Cylindrical Shell ◽  
Cylindrical Shells ◽  
Continuous Functions ◽  
Functionally Graded ◽  
Graded Materials ◽  
Graded Material ◽  
Circular Cylindrical Shells

Based on the Loves shell theory, relationship between bending solutions of functionally graded materials (FGM) and homogenous circular cylindrical shells was studied. By comparing the displacement-type governing equations for axially symmetrically bending of FGM and homogenous circular cylindrical shells, an analogous transform relation between the deflections of FGM circular cylindrical shell and those of homogenous one was obtained. By giving the material properties of FGM circular cylindrical shell changing as continuous functions in the thickness direction, the corresponding transition factor between the solutions of the two kind circular cylindrical shells were derived, which reflect the non-uniform properties of the functionally graded material circular cylindrical shell. Numerical example shows that the numerical solutions of the maximum of non-dimensional deflections are almost in agreement with the transformational solutions whennequals approximately 5, wherenis the volume fraction index. As a result, solutions for axially symmetrically bending of a non-homogenous circular cylindrical shell can be reduced to that of a homogenous one and the calculation of the transformation factors.

Buckling of Circular Cylindrical Shells Using a Displacement Function

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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