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对超音速来流中的四边简支粘弹性夹层壁板颤振问题进行了研究。基于Kelvin-Voigt粘弹性本构模型、小变形理论和一阶气动力活塞理论建立了三维粘弹性夹层壁板的气动弹性颤振方程。使用Galerkin方法将粘弹性夹层壁板气动力方程简化,并使用数值方法进行求解。讨论了粘弹性阻尼、来流动压和夹心层厚度对颤振特性的影响。研究表明:(1)随着来流动压的增大,系统一阶频率增大,二阶频率减少,一阶频率和二阶频率相等后,系统阻尼变为两个分支,系统某一分支阻尼为零时,系统发生颤振,此时来流动压为颤振临界动压。(2)随着粘弹性阻尼系数的增大,系统的频率有所减小,但影响远不及夹心层占总厚度比值的影响大。(3)随着夹心层厚度的增大,系统的临界颤振动压减小。
The flutter problem of the simply supported viscoelastic sandwich panels in the supersonic incoming flow was studied. Based on Kelvin-Voigt viscoelastic constitutive model, small deformation theory and first-order aerodynamic piston theory, the aeroelastic flutter equation of three-dimensional viscoelastic sandwich panels is established. The aerodynamic equation of viscoelastic sandwich panel is simplified by Galerkin method and solved numerically. The effects of viscoelastic damping, inflow pressure and sandwich thickness on flutter characteristics are discussed. The results show that: (1) With the increase of the incoming flow pressure, the first-order frequency of the system increases and the second-order frequency decreases. After the first-order and second-order frequencies are equal, the system damping becomes two branches. Is zero, the system chatter occurs, this time to flow pressure flutter critical dynamic pressure. (2) With the increase of viscoelastic damping coefficient, the frequency of the system is reduced, but the influence is far less than that of the sandwich layer in the total thickness ratio. (3) As the thickness of the sandwich increases, the dynamic pressure of the critical flutter of the system decreases.