Impulsive Responses of a Circular Cylindrical Shell Subjected to Waterhammer Waves

1991 ◽  
Vol 113 (4) ◽  
pp. 517-523 ◽  
Author(s):  
T. Adachi ◽  
S. Ujihashi ◽  
H. Matsumoto
Keyword(s):  
Cylindrical Shell ◽  
Perfect Fluid ◽  
Analytical Solutions ◽  
Shell Theory ◽  
Coupling Effect ◽  
Circular Cylindrical Shell ◽  
Inertia Effect ◽  
Pipe Coupling ◽  
Rough Approximation ◽  
Coupled Theory

The impulsive responses of semi-finite and finite pipes filled with fluid are analyzed in order to clarify the validity of Joukowsky’s theory and the fluid-pipe coupling effect. In the analysis, Flu¨gge’s dynamic bending shell theory and the potential theory of compressible perfect fluid are used. The analytical solutions in Laplace transformed domain are obtained. The inversion of the solutions is performed numerically using the algorithm of FFT. When a pipe is fairly long, it is shown that the result of Joukowsky’s theory which has no pipe inertia effect approximately agrees with that of the coupled theory. When a pipe is short, Joukowsky’s theory shows rough approximation of the responses. The response of the uncoupled theory with the inertia of a pipe is different from that of the coupled theory for both long and short pipes.

Electromechanical Coupling and Signal Distribution of a Circular Cylindrical Shell Coupled With Segmented Sensors

2008 ◽  
Author(s):  
Shih-Lin Huang ◽  
Chin-Chou Chu ◽  
Chien C. Chang ◽  
H. S. Tzou
Keyword(s):  
Cylindrical Shell ◽  
Large Scale ◽  
Electromechanical Coupling ◽  
Coupling Effect ◽  
Circular Cylindrical Shell ◽  
Open Circuit ◽  
Signal Generation ◽  
Signal Distribution ◽  
Shear Design ◽  
Spatially Distributed

The direct piezoelectric effect has long been recognized as an effective electromechanical coupling effect applied to designs of various transducers. Conventional sensor design usually follows three design principles: 1) the tension/compression design, 2) the bending or flexible design and 3) the shear design. These are mostly point-type transducers monitoring responses of discrete locations and, thus, they are not suitable to dynamic spatial monitoring of large-scale distributed structures, such as shells and plates. Accordingly, distributed designs and configurations, such as the segmentation and shaping techniques, have been proposed and evaluated in the last two decades. This study is to evaluate electromechanical coupling and signal generations of a coupled piezoelectric/elastic circular shell structure. A generic open-circuit signal equation of electromechanical coupling and signal generation is presented first, followed by a simplification to signal generation of a circular cylindrical shell case. The total signal generation and its contributing components are analyzed in the modal domain. Spatially distributed modal signals of various shell modes are calculated and the spatial signal distribution illustrates distinct modal characteristics resulting from microscopic modal strain behaviors. Thus, the optimal sensor location(s) for specific shell modes can be identified from the modal signal distribution plots.

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.

Free vibration of bi-material cylindrical shells

2016 ◽  
Vol 230 (15) ◽  
pp. 2637-2649 ◽  
Author(s):  
Saeed Sarkheil ◽  
Mahmud S Foumani ◽  
Hossein M Navazi
Keyword(s):  
Exact Solution ◽  
Cylindrical Shell ◽  
Free Vibration ◽  
Boundary Conditions ◽  
State Space ◽  
Thin Shell ◽  
Shell Theory ◽  
Circular Cylindrical Shell ◽  
Space Technique ◽  
Thin Shell Theory

Based on the Sanders thin shell theory, this paper presents an exact solution for the vibration of circular cylindrical shell made of two different materials. The shell is sub-divided into two segments and the state-space technique is employed to derive the homogenous differential equations. Then continuity conditions are applied where the material of the cylindrical shell changes. Shells with various combinations of end boundary conditions are analyzed by the proposed method. Finally, solving different examples, the effect of geometric parameters as well as BCs on the vibration of the bi-material shell is studied.

Traveling Wave Vibration of Rotating Thin Circular Cylindrical Shell

2012 ◽  
Vol 226-228 ◽  
pp. 262-266 ◽  
Author(s):  
Yan Qi Liu ◽  
Fu Lei Chu
Keyword(s):  
Cylindrical Shell ◽  
Frequency Response ◽  
Traveling Wave ◽  
Shell Theory ◽  
Circular Cylindrical Shell ◽  
Radial Excitation ◽  
Forward Wave ◽  
Frequency Responses ◽  
Amplitude Frequency Response ◽  
Love’S Shell Theory

In this paper, the vibration characteristics of the rotating thin circular cylindrical shell subjected to the radial excitation are presented. Based on the Love’s shell theory, the governing equation of the rotating thin circular cylindrical shell is derived by using the Hamilton’s principle. Then, the amplitude-frequency responses for traveling wave vibration of the circular cylindrical shell are investigated. The results indicate that there exists the traveling wave vibration for the rotating thin circular cylindrical shell, namely: the forward wave and the backward wave. The effects of the damping and excitation on the amplitude-frequency response are analyzed.

Stresses Emanating From the Supports of a Cylindrical Shell Produced by a Lateral Pressure Pulse

1972 ◽  
Vol 39 (1) ◽  
pp. 124-128 ◽  
Author(s):  
M. J. Forrestal ◽  
G. E. Sliter ◽  
M. J. Sagartz
Keyword(s):  
Cylindrical Shell ◽  
Shell Theory ◽  
Pressure Pulse ◽  
Integral Transform ◽  
Circular Cylindrical Shell ◽  
Radial Pressure ◽  
Rectangular Pulse ◽  
Wave Fronts ◽  
Timoshenko Type ◽  
Stress Resultant

A semi-infinite, elastic, circular cylindrical shell is subjected to two uniform, radial pressure pulses, one a step pulse and the other a short-duration, rectangular pulse. Solutions for the stresses emanating from both a clamped support and a simple support are presented for a Timoshenko-type shell theory and a shell bending theory. Results from the Timoshenko-type theory are obtained using the method of characteristics, and results from the shell bending theory are obtained using integral transform techniques. Numerical results from both shell theories are presented for the bending stress and the shear stress resultant. Results show that the effects of rotary inertia and shear deformation are important only in the vicinity of the wave fronts. However, if the duration of the pressure pulse is short, maximum stresses can occur in the vicinity of the wave fronts where a Timoshenko-type shell theory is required for realistic response predictions.

Forced Plane Strain Motion of Cylindrical Shells—A Comparison of Shell Theory With Elasticity Theory

1973 ◽  
Vol 40 (3) ◽  
pp. 725-730 ◽  
Author(s):  
P. S. Pawlik ◽  
H. Reismann
Keyword(s):  
Cylindrical Shell ◽  
Analytical Solution ◽  
Elasticity Theory ◽  
Plane Strain ◽  
Outer Surface ◽  
Shell Theory ◽  
Circular Cylindrical Shell ◽  
Initial Response ◽  
Linear Elasticity Theory ◽  
Specific Loading

A radially directed load is suddenly applied to a portion of the outer surface of a circular cylindrical shell which responds in a state of plane strain. An analytical solution for the resulting dynamic response is obtained within the context of linear elasticity theory, Flu¨gge shell theory, and an “improved” shell theory. A comparison of results for specific loading conditions indicates that the improved theory is far superior to the Flu¨gge theory in terms of predicting both the magnitude and characteristics of the response. However, as expected, neither shell theory satisfactorily predicts the wave character of the initial response.

scholarly journals Application of Uniformly Valid Shell Theory

2021 ◽  
Author(s):  
Samuel W Chung ◽  
Hyun-ho Ju
Keyword(s):  
Cylindrical Shell ◽  
Internal Pressure ◽  
Constitutive Equations ◽  
Shell Theory ◽  
Epoxy Composite ◽  
Circular Cylindrical Shell ◽  
Arbitrary Orientation ◽  
Composite Layers ◽  
Different Thickness

For the purpose of demonstrating the applicability of the previously derived theories, the problem of a laminated circular cylindrical shell under internal pressure and edge loadings will be examined. The cylinder is assumed to consist of boron/epoxy composite layers. Each layer is taken to be homogeneous but anisotropic with an arbitrary orientation of the elastic axes. We need not consider the restriction of the symmetry of the layering due to the non-homogeneity considered in the original development of the theory expressed by the constitutive equations. Thus, each layer can possess a different thickness.

scholarly journals Application of Uniformly Valid Shell Theory

2021 ◽  
Author(s):  
Samuel W Chung ◽  
Hyun-ho Ju
Keyword(s):  
Cylindrical Shell ◽  
Internal Pressure ◽  
Constitutive Equations ◽  
Shell Theory ◽  
Epoxy Composite ◽  
Circular Cylindrical Shell ◽  
Arbitrary Orientation ◽  
Composite Layers ◽  
Different Thickness

For the purpose of demonstrating the applicability of the previously derived theories, the problem of a laminated circular cylindrical shell under internal pressure and edge loadings will be examined. The cylinder is assumed to consist of boron/epoxy composite layers. Each layer is taken to be homogeneous but anisotropic with an arbitrary orientation of the elastic axes. We need not consider the restriction of the symmetry of the layering due to the non-homogeneity considered in the original development of the theory expressed by the constitutive equations. Thus, each layer can possess a different thickness.

Dynamic Response Analysis and Comparative Study of Circular Cylindrical Shell Subjected to Radial Impact

2007 ◽  
Vol 51 (02) ◽  
pp. 94-103
Author(s):  
Li Xuebin
Keyword(s):  
Cylindrical Shell ◽  
Dynamic Response ◽  
Normal Mode ◽  
Shell Theory ◽  
Circular Cylindrical Shell ◽  
Equations Of Motion ◽  
Response Analysis ◽  
Mode Theory ◽  
Normal Mode Theory ◽  
Exact Derivation

Following Flu¨ gge's exact derivation for the buckling of cylindrical shells, the equations of motion for dynamic loading of a circular cylindrical shell under external hydrostatic pressure have been formulated. The normal mode theory is used to provide transient dynamic response for the equations of motion. The responses of displacements, strain, and stress are obtained for the area of impact, while those outside the area of impact are also calculated. The accuracy of normal mode theory and Timoshenko shell theory are examined in this paper.

Free Vibration Analysis of Orthotropic Circular Cylindrical Shell Under External Hydrostatic Pressure

2002 ◽  
Vol 46 (03) ◽  
pp. 201-207
Author(s):  
Li Xuebin ◽  
Chen Yaju
Keyword(s):  
Cylindrical Shell ◽  
Hydrostatic Pressure ◽  
Free Vibration ◽  
Material Properties ◽  
Shell Theory ◽  
Circular Cylindrical Shell ◽  
Free Vibration Analysis ◽  
Free Vibrations ◽  
External Hydrostatic Pressure ◽  
Two Parameters

An analysis is presented for the free vibration of an orthotropic circular cylindrical shell subjected to hydrostatic pressure. Based on Flügge shell theory, the equations of free vibrations of an orthotropic circular cylindrical shell under hydrostatic pressure are obtained. For shear diaphragms at both ends, the resulting characteristic equations about pressure and frequency are given. These two parameters are calculated exactly. The effect of the shell's parameters (L/R, h/R) and material properties on the free vibration characteristics are studied in detail. Differences between Love-Timoshenko, Donnell equations and that of the Flügge theory are examined as well.

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