| With the advent of advanced composite materials, the free vibrations of composite beams which are generally used as structural elements in the idealization of high aspect ratio composite wings has inspired continuing research interest, particularly amongst the aeroelasticians. This is because the free vibration characteristics generally affect the aeroelastic properties, and importantly for composite wings, such characteristics can be altered or changed favorably by suitable choice of ply orientations and stacking sequence. So, the research of this subject has a large significance. The paper mainly studies the dispersion characteristics, the free vibration characteristics and the vibration power flow characteristics of the composite Euler beam. The paper is organized as follows.Firstly, review the history of the composite material, the research progress of vibration characteristics of the Euler beam, and the research overview of the vibration power flow.Secondly, research the dispersion characteristics of an infinite composite Euler beam, the paper presents the effect of coupling between bending and torsion deformations on vibrations of composite Euler-Bernoulli beams from a wave vibration standpoint. In the study, it is found that the torsion mode is only unaffected by the material coupling at low frequencies. The flexural modes are found affected over the entire frequency band.Thirdly, from the analysis of the free vibration of the beam, it is found that the bending vibration is more sensitive to material coupling than torsion vibration. Among bending modes, the higher frequency modes are far more sensitive to such a coupling effect.Then, by calculating the input power flow of the beams, it is found that the input power flow become higher with the material coupling coefficient become higher, furthermore the frequency band of the wave vibration become wider . The last, summarize the paper and give the expect ions of the future research.
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