关键词: 随机颤振, 非线性系统, 随机分叉, 白噪声, Lyapunov指数

Abstract: This article examines the dynamical behavior of stochastic flutter of binary airfoil that is excited by a Gauss white noise by means of numerical simulation. Firstly, the airfoil is modeled as a flat plate in a linear constant incompressible flow under a Gauss white noise excitation. The plate is with two degrees of freedom on heave and pitch and with a structural type nonlinearity in the form of a cubic hardening torsional spring. Secondly, a Monte Carlo simulation is performed to solve the system of random differential equations. And then based on the numerical result, a statistic analysis is made and the maximal Lyapunov exponent of the relevant system is obtained. Finally, it is found that the dynamical behavior of a nonlinear structural airfoil excited by a Gauss white noise is dramatically different from that of a deterministic system and its stochastic flutter point is always ahead of the point of the deterministic flutter.

Key words: stochastic flutter, nonlinear system, stochastic bifurcation, white noise, Lyapunov exponent