Abstract:The application of FEM is shown for free vibration analysis of moderately thick laminated composite plates with edges elastically restrained against translation and rotation. The governing equations employed are based on the first order shear deformation theory including the effects of rotary inertia. Several combinations of translational and rotational elastic edge constraints are considered. Convergence study with respect to the number of nodes has been carried out and the results are compared with those from past investigations available only for simpler problems. Angle-ply and cross-ply laminates with different thickness-to-length ratios are examined. Comparisons are made with results for thin as well as moderately thick laminated plates.
Cutouts are commonly used as access port for mechanical and electrical structures. Most of the structures generally work under severe dynamic loading and different constrained conditions during their service life. This may lead to vibration of the structure. Therefore, it is necessary to predict the vibration responses of laminated composite plates with cutouts precisely with less computational cost and good accuracy of these complex structures. A suitable finite element model is proposed and developed based on first order shear deformation theory using ANSYS parametric design language (APDL) code. The model has been discretized using an appropriate eight nodded element (SHELL 281) from the ANSYS element library. The free vibrations are computed using Block-Lanczos algorithm. The convergence study has been done of the developed model and compared with those available published literature. Effects of different geometric parameters (aspect ratio, thickness ratio, boundary conditions, number of layers, angle of lamina geometry of cutout, cutout side to plate side ratio and distance between cutouts) and material properties on the free vibration responses are discussed in detail. The frequency increases with increase in the number of layers, modulus ratio of plate and angle of lamina. The frequency decreases with increase in aspect ratio, thickness ratio, size of cutout and distance between cutouts. The boundary conditions of the plate play an important role in the free vibrations of the plate with cutouts. The Non-dimensional frequencies are higher for fully clamped boundary condition in comparison to other boundary conditions.
This paper presents the free vibration analysis of stiffened isotropic plate by means of finite element method. Stiffeners are used in plates to increase the strength and stiffness. The effect of position of stiffeners on isotropic plate has been studied which involve the possible combination of clamped and free edge condition. The model has been discretized using a 20-node solid element (SOLID186) from the ANSYS element library. The natural frequencies are calculated using Block-Lanczos algorithm. The comparisons of stiffened plate with the available results are found to be in good uniformity. The effect of different boundary conditions, stiffeners location, thickness ratio, stiffener thickness to plate thickness and aspect ratio on the vibration analysis of stiffened plates has been studied.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.