Effect of fibre volume on the natural frequencies of laminated composite plate

Abstract

Resonance is an important phenomenon related to natural frequencies that could lead to catastrophic failure, and therefore investigating this phenomenon is crucial. There have been many studies regarding the effect of stiffness on the natural frequencies of laminated composite plates; however, studies relating the fibre volume to the natural frequencies have still not been established. This paper aims to investigate the effect of fibre volume on the natural frequencies of laminated composite plates. A 300 mm × 300 mm plate model made of carbon/epoxy composite laminates under Clamp-Free-Clamp-Free (CFCF) boundary conditions was developed using Finite Element Software (ANSYS). Different lamination schemes (fibre orientations, symmetry and anti-symmetry lay-up) with various fibre volume fractions were the analysed parameters. The natural frequencies were calculated for each scenario using finite element simulations. The mode shapes of vibration of the plates were also examined. To establish the precise finite element model for free vibration analysis of laminated composite plates, convergence analysis and numerical verification were conducted. The present numerical simulation results were in good agreement with published numerical results. The findings demonstrated that increasing the fibre capacity results in an increase of all vibrational modes and their shapes. Aside from that, the fibre orientation at 90°had the highest natural frequency value (910.52 Hz, 915.66 Hz and 1332.2 Hz) and the lowest natural frequency value at 0° (244.84 Hz, 245.90 and 627.95 Hz) for the first three modes shape of vibrations. In general, this study has made important contributions on how a fibre volume affects the natural frequencies of laminated composite plates.