In this study, the effects of stacking sequence, element type, and mesh size on modal analysis of laminated composite plates were analyzed using finite element and Taguchi methods. Plates have eight plies. Left side of the plates was assumed to be clamped boundary conditions and other edges were designed to be free boundary conditions. Fundamental frequency characteristics were performed using finite element software ANSYS Parametric Design Language (APDL). The arrangements of plies and analyses were conducted using Taguchi’s L8 orthogonal array with two levels for each control factor. Stacking sequence, element type, and mesh size were assumed to be control factors with two levels. Analysis of signal-to-noise (S/N) ratio was used in order to see the effects of control factors. Analysis of variance (ANOVA) was carried out in order to determine the significant levels of the control factors. According to results, the first mode frequency results of the laminated composite plates with symmetric plies are higher than plates with antisymmetric plies. SHELL281 element type is more sensitive than SHELL181 element type for free vibration analyses. The increase of mesh size provides the increase of the sensitivity of the finite element analysis of free vibration. According to ANOVA at 95 % confidence level, the most strongly control factors on the fundamental frequency were determined as stacking sequence with 96.90 %, mesh size with 1.61 %, and element type with 0.76 % respectively. The stacking sequence and mesh size on modal analysis are significant control factors due to P-value < 0.05 value whereas element type is non-significant control factor. Based on the comparison of numerical and predictive results, the minimum difference was calculated for third analysis whereas the maximum difference was determined for fourth and sixty analyses. The minimum affected zone of the plates is the clamped edge of the laminated composite plates.
Anahtar Kelimeler: Laminated Composite Plates, Modal Analysis, Finite Element Method, Taguchi Technique
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