曲率对圆柱形扁壳颤振临界动压的影响

Curvature Effects on Flutter Critical Aerodynamic Pressures of Shallow Cylindrical Shells

为研究曲率对圆柱形扁壳在超声速轴向气流中的颤振行为的影响,采用活塞理论计算超声速气动力,建立了圆柱形扁壳的超声速气动弹性运动方程。采用二维微分求积法(DQM)离散方程,运用特征值方法分析了不同曲率下线性系统的颤振临界动压。结果表明,在长宽比不变的情况下,随着曲率的增加,越来越多的低阶频率在周向上分布越密集,颤振的频率也随之增大。随着曲率的增大,颤振临界动压呈指数增长。

The curvature effects on the flutter critical aerodynamic pressure were investigated. Using the piston theory to calculate supersonic flow, the aeroelastic equations of the shallow cylindrical shells were established. Two-dimensional differential quadrature method was used to discretize the motion equations. The curvature effects on the flutter critical aerodynamic pressures were studied by eigenvalue analysis. The results show that, with the increase of curvature, more and more low orders of frequencies are arranged in the circumferential direction, and the frequency of the flutter is also increased. With the increase of curvature, the critical dynamic pressure of flutter grows exponentially.