有界噪声与谐和激励联合作用下Duffing-Rayleigh振子的Melnikov混沌

Melnikov chaos in Duffing-Rayleigh oscillator subjected to combined bounded noise and harmonic excitations

研究了有界噪声与谐和激励作用下的Duffing-Rayleigh振子的动力学行为.首先运用随机Melnikov过程方法得到系统出现混沌的条件,结果表明随着非线性阻尼参数的增加系统会从混沌运动到周期运动,随着Wiener过程强度参数的增加,系统由混沌进入周期的临界幅值会先递增后不变.最后,用两类数值方法即最大Lyapunov指数与Poincare截面验证了上述结果.

In this paper,the dynamic behavior of Duffing-Rayleigh oscillator subjected to combined bounded noise and harmonic excitations is investigated. Theoretically, the random Melnikov＇s method is used to establish the conditions of existence of chaotic motion. The result implies that the chaotic motion of the system turns into the periodic motion with the increase of nonlinear damping parameter, and the threshold of random excitation amplitude for the system to change from chaotic to periodic motion in the oscillator turns from increasing to constant as the intensity of the noise increases. Numerically,the largest Lyapunov exponents and the Poincare maps are also used for verifying the conclusion.