The Effect of Ply Orientation on the Vibration Characteristics of ‘T’ Stiffen Composite Panel: A Finite Element Study

Opukuro David-West


Aircraft producers have extensively adopted the use of T-shaped stiffened fibre reinforced composite panels in the thin walled structures such as the fuselage and wings. The composite materials present the advantage of high specific strength and stiffness ratios, coupled with weight reduction compare to traditional materials. This report presents a numerical study about the free-free vibration analysis of T-stiffened carbon fibre reinforced epoxy composite panels with surface and identical ply orientations of 00, 150, 300, 450, 600, 750 and 900 using ANSYS 17 finite element code and the results presented herein. The fundamental frequencies increase to a peak and then decrease taking the form a half sine curve. The dynamic analysis was realized using the Lanczos tool to extract the mode shapes and natural frequencies.

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Available from: Accessed: 12th August 2016.

Available from:, Accessed: 12th August 2016.