Effects of Symmetric and Antisymmetric Fiber Orientations on the Natural Frequencies of FRP Aircraft Panel Boards

Abstract

An aircraft instrument panel board is housing high precision instruments and the vibration of the panel board, which is fitted to the aircraft frame, affects their performance. The amplitudes of this vibration can be reduced if the natural frequencies of the panel boards are kept away from the operating frequencies of the aircraft so that the occurrence of resonance can be avoided at low frequency ranges. This paper presents the experimental investigations conducted on the free vibration characteristics of composite (E-glass–Poly Vinyl Ester) aircraft instrument panel boards. These boards are prepared by hand layup technique and their physical properties, elastic properties and the first three natural frequencies are determined experimentally. These natural frequencies are also obtained using a FEM software package and compared with the experimental results for their dependability. The natural frequencies of the composite panel board for symmetric, and antisymmetric glass fiber orientations for different fiber orientations and for odd and even number of layers are determined and the results obtained are discussed.

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References

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