双频信号驱动含分数阶内、外阻尼Duffing振子的振动共振

本文利用解析和数值的方法研究了由双频周期信号驱动含分数阶内、外阻尼的Duffing振子的振动共振现象，并讨论了分数阶阶数对上述现象的影响. 研究发现：双频周期信号同时驱动的分数阶Duffing振子响应幅值增益Q可随着高频周期激励幅值的改变达到最大值，即出现了和整数阶非线性动力系统相似的振动共振现象，而相应的分数阶导数项则分别为系统提供了内、外两种阻尼力从而导致了系统有效势函数的改变，进而引发了比整数阶动力系统更为丰富的振动共振现象. 关键词： 振动共振 Duffing振子 分数阶阻尼 分数阶系统

Vibrational resonance in a Duffing system with fractional-order external and intrinsic dampings driven by the two-frequency signals

The phenomenon of vibrational resonance (VR) in a Duffing system with both fractional-order external damping and fractional-order intrinsic damping driven by the two-frequency periodic signals is investigated. It is observed that the resonance amplitude Q can be optimized by an appropriate choice of the amplitude of the high-frequency signal. The obtained relationship between VR and the fractional-orders shows that both fractional-order external damping and fractional-order intrinsic damping can induce changes of the shapes of the effective potential function and then lead to more abundant resonance behaviors than in the traditional dynamic systems.