分数阶质量涨落谐振子的共振行为

针对黏性介质引起的Brown粒子质量存在随机涨落以及阻尼力对历史速度具有记忆性等问题, 本文首次提出分数阶质量涨落谐振子模型, 以考察黏性介质中Brown粒子的动力学特性. 首先, 将Shapiro-Loginov 公式分数阶化, 使之适用于对含指数关联随机系数的分数阶随机微分方程的求解. 然后, 利用随机平均法和分数阶Shapiro-Loginov公式推导系统稳态响应振幅的解析表达式, 并据此研究系统的共振行为; 最后, 通过仿真实验验证理论结果的可靠性. 研究表明: 1)质量涨落噪声可诱导系统产生随机共振行为; 2)记忆性阻尼力可诱导系统产生参数诱导共振行为; 3)不同参数条件下, 系统表现出单峰共振、双峰共振等多样化的共振形式. 关键词： 黏性介质 质量涨落 阻尼记忆性 分数阶谐振子

The resonant behavior of fractional harmonic oscillator with fluctuating mass

When moving in viscous medium, the mass of a Brownian particle is fluctuant and its damping force depends on the past velocity history. Therefore, in order to investigate the characteristics of Brownian motion in viscous medium, fractional harmonic oscillator is proposed in this paper for the first time so for as we know. First, the Shapiro-Loginov formula is fractionized to solve fractional stochastic differential equation with exponential correlative stochastic coefficients. Then, by using stochastic averaging method and fractional Shapiro-Loginov formula, the analytical expression of a system’s steady response amplitude is presented and the system’s resonant behavior is discussed accordingly. Finally, the reliability of theoretical results is tested by simulation experiments. All the research shows that: (1) Stochastic resonant behavior can be induced by mass fluctuation noise. (2) Parameter-induced resonance can be induced by memory damping force. (3) Under different parameter conditions, the system’s resonant forms are diverse.
Keywords： viscous medium mass fluctuation memory damping force fractional harmonic oscillator