Parametric Resonance Characteristics of Laminated Composite Curved Shell Panels in a Hygrothermal Environment (original) (raw)
Related papers
Journal of Reinforced Plastics and Composites, 2001
The parametric resonance characteristics of laminated composite doubly curved panels subjected to various in-plane static and periodic compressive edge loadings, including partial and concentrated edge loading are studied using finite element analysis. The first order shear deformation theory is used to model the doubly curved panels, considering the effects of transverse shear deformation and rotary inertia. The theory used is the extension of dynamic, shear deformable theory according to the Sander's first approximation for doubly curved laminated shells, which can be reduced to Love's and Donnell's theories by means of tracers. The effects of number of layers, static load factor, side to thickness ratio, shallowness ratio, boundary conditions, degree of orthotropy, ply orientations and various load parameters on the principal instability regions of doubly curved panels are studied in detail using Bolotin's method. Quantitative results are presented to show the effects of shell geometry, lamination details and load parameters on the stability boundaries. Results of plates and cylindrical shells are also presented as special cases and are compared with those available in the literature.
Parametric Resonance Characteristics of Laminated Composite Twisted Cantilever Panels
2008
The present study deals with the parametric resonance behaviour of laminated composite curved shell panels in a hygrothermal environment using Bolotin's approach. A simple laminated model is developed using first order shear deformation theory (FSDT) for the vibration and dynamic stability analysis of laminated composite shells subjected to hygrothermal conditions. A computer program based on the finite element method (FEM) in a MATLAB environment is developed to perform all necessary computations. Quantitative results are presented to show the effects of curvature, ply-orientations, degree of orthotropy and geometry of laminates on the parametric instability of composite curved shell panels for different temperature and moisture concentrations. The excitation frequencies of laminated composite panels decrease with the increase of temperature and moisture due to reduction of stiffness for all laminates.
Parametric Instability of Composite Curved Panel Subjected to Concentrated Edge Loading
2003
The parametric resonance characteristics of laminated composite curved panels subjected to various in-plane periodic concentrated edge loadings are studied using finite element analysis. The first order shear deformation theory is used to model the curved panels, considering the effects of transverse shear deformation and rotary inertia. The effects of number of layers, static load factor, boundary conditions and ply orientations for different positions of loading on the principal instability regions of curved panels are studied in detail using Bolotin's method. Quantitative results are presented to show the effects of shell geometry, lamination details and load parameters on the stability boundaries. Key words-Parametric resonance, composite, concentrated loading, instability region
Parametric Resonance Characteristics of Angle-Ply Twisted Curved Panels
International Journal of Structural Stability and Dynamics, 2008
The present study deals with the dynamic stability of laminated composite pre-twisted cantilever panels. The effects of various parameters on the principal instability regions are studied using Bolotin's approach and finite element method. The first-order shear deformation theory is used to model the twisted curved panels, considering the effects of transverse shear deformation and rotary inertia. The results on the dynamic stability studies of the laminated composite pre-twisted panels suggest that the onset of instability occurs earlier and the width of dynamic instability regions increase with introduction of twist in the panel. The instability occurs later for square than rectangular twisted panels. The onset of instability occurs later for pre-twisted cylindrical panels than the flat panels due to addition of curvature. However, the spherical pre-twisted panels show small increase of nondimensional excitation frequency.
Dynamic Stability of Laminated Composite Twisted Curved Panels
2006
The twisted cantilever panels have significant applications in wide chord turbine blades, compressor blades, fan blades, particularly in gas turbines. This range of practical applications demands a proper understanding of their vibration, static and dynamic stability characteristics. Due to its significance, a large number of references deal with the free vibration of twisted plates. Structural elements subjected to in-plane periodic forces may lead to parametric resonance, due to certain combinations of the values of load parameters. The instability may occur below the critical load of the structure under compressive loads over wide ranges of excitation frequencies. Composite materials are being increasingly used in turbo-machinery blades because of their specific strength, stiffness and these can be tailored through the variation of fiber orientation and stacking sequence to obtain an efficient design. Thus the parametric resonance characteristics of laminated composite twisted ca...
Dynamic Stability of Laminated Composite Curved Panels with Cutouts
Journal of Engineering Mechanics, 2003
The present investigation deals with the dynamic stability behavior of laminated composite curved panels with cutouts subjected to in-plane static and periodic compressive loads, analyzed using the finite element method. A generalized shear deformable Sanders' theory with tracers is used in this study. Numerical results obtained for vibration and buckling of composite panels with cutouts compare well with literature. The principal dynamic instability region of composite perforated panels is obtained using Bolotin's approach. The study reveals that curved panels with cutouts depict higher stiffness with the addition of curvatures. The laminated hyperbolic paraboloid panel shows the highest stiffness with the onset of instability at higher excitation frequencies. The effect of curvature in laminated composite curved panels is reduced with an increase in size of the cutout. The principal instability regions are influenced by the lamination parameters. Thus, the laminate construction, coupled with cutout geometry, can be used to the advantages of tailoring during design of composite structures for practical applications.
Acta Mechanica, 2014
Your article is protected by copyright and all rights are held exclusively by Springer-Verlag Wien. This e-offprint is for personal use only and shall not be self-archived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. You may further deposit the accepted manuscript version in any repository, provided it is only made publicly available 12 months after official publication or later and provided acknowledgement is given to the original source of publication and a link is inserted to the published article on Springer's website. The link must be accompanied by the following text: "The final publication is available at link.springer.com".
In the present work, analytical solutions for laminated composite doubly curved panels on rectangular plan form undergoing small deformations and subjected to uniformly distributed transverse load have been obtained. The problem is formulated using first order shear deformation theory. The spatial descretization of the linear differential equations is carried out using fast converging finite double Chebyshev series. The effect of panel thickness, curvature, boundary conditions, lamination scheme as well as material property on the static response of panel has been investigated in detail. doubly curved panel, analytical, Chebyshev, static, rectangular plan form PACS number(s): 46.25.-y, 46.70.De, 81.05.Qk