Numerical modelling of parametric instability problem for composite plate using finite element method

Abstract

Abstract. The application of laminated sandwich composite in machine structures is attractive due to the low specific and tailorable properties of the composites. As such a study on the parametric instability that often occurs in machine structures should be crucially conducted on composite plates. In this paper, finite element method (FEM) has been used to model laminated composite plate subjected to periodic compressive loading for the parametric instability analysis. The FEM formulation is based on the first order shear deformation theory. Eight noded serendipity element that requires 5 degrees of freedom per node is used in this study. The developed Mathieu-Hill type equation that represents the parametric instability of the composite plate has been solved using the Bolotin's method that reduces the Mathieu-Hill equation to a couple of eigen-value problems. The FEM source codes have been developed to determine the instability charts for several configurations of composite plates. While the formulation and codes have been found to give results that agree well with past results, it has been also been found that as the static load factor is increased, the frequency center for dynamic instability region is shifted to the left while the degree of instability is increased.

Similitude of a Damped Vibrating Composite Plate

“…A structural composite is a material system consisting of two or more phases on a macroscopic scale whose mechanical performance and properties are designed to be superior to those of the constituent materials acting independently. One of these phases is stiffer and stronger and is called reinforcement and the less stiff and weaker phase is known as matrix: the illustration of a composite plate is shown in the Figure 1 [1], where the reference system (O,x,y,z) is the reference system of the laminate, (O,1,2,3) is the local reference system of the laminate based on the arrangement of the fibres at θ angle to the reference system of the laminate, a, b, t are, respectively, the length, width and thickness of the plate. Damping in fiber-reinforced composite materials can be Figure 1.…”

“…There are many sources of energy dissipation in fiber-reinforced composite material: the viscoelastic nature of its components, presence of damages like a crack in matrix (as discussed in [2] damping is more sensitive than stiffness due to the damage in composite materials), broken fiber, slip between fiber and matrix interface [3]. Two additional contributes have to be also considered: (1) Damping due to the viscoplasticity, i.e. fiber-reinforced composite material exhibit nonlinear damping due to the presence of high stress and strain at large amplitudes of vibration, and (2) damping due to the thermoelasticity, i.e.…”

Natural Frequencies Optimisation of Hybrid Composite Laminates using Response Surface Method

“…An investigation about the effects of different fibre volume fraction ratios had also been conducted by Pingkular and Suresha [3] while several stacking sequences on hybrid laminates' natural frequency had been conducted by Madhu and Kumarasamy [20]. In addition, mode shape and natural frequency had also been studied for hybrid laminate composites such as Glass-epoxy, Carbon-epoxy and Graphite fibre reinforced polyimide materials by Suragimath [21], E-Glass fibre 60% and Kevlar 40% by Jadhav et al, [22] and laminated composites hybrid with Shape Memory Alloy (SMA) materials by Yusof et al, [23]. This study is novel as to date, no identical method has been published in literature for analysing the natural frequency of Carbon/Glass hybrid laminates with different lamination schemes, fibre angles and ply thickness.…”

Dynamic analysis of an orthotropic viscoelastic cylindrical panel of variable thickness

“…The study of composite plates subjected to periodic compressive loads is considered in [7]. Based on the finite element method, the Mathieu-Hill equation is solved.…”