外力调制下壳模型阵发混沌的相变行为

The Phase Transition Behavior of Intermittent Chaos in Shell Model under Modulation of External Force

研究了Gledzer-Ohkitani-Yamada模型在周期外力和反馈外力调制下的相变和稳定性.外周期力的调制强度和调制周期都会影响准周期到混沌的相变行为.若固定调制周期,则临界点随调制强度的增大而增大,并且随着调制强度逐渐增强,临界点对于调制强度的依赖由非线性变为准线性.若固定调制强度,则调制周期的增加可以增强系统的稳定性.在反馈外力的作用下,弱调制就可以产生强共振并影响系统的稳定性.

The phase transition and stability of Gledzer-Ohkitani-Yamada model forced by modulated periodic external force and feedback force is investigated. Both the modulated intension and period of periodic external force can influence the phase transition from quasi-periodic state to intermittent chaos. If the modulated period is fixed, the critical value will increase along with the modulated intension increased. Furthermore, along with the increasing of modulated intension, the reliance of critical value on modulated intension changes from nonlinear function into quasi-linear function. If the modulated period is fixed, the increase of modulated period can strengthen the stability of syster. Under the function of feedback, week modulation can produce the strong resonance in the model and influence the stability of system.