非线性涡动时裂纹转子的分叉与浑沌特性研究

NONLINEAR INFLUENCES OF WHIRL SPEED ON BIFURCATION AND CHAOS OF CRACKED ROTOR

分析非线性涡动裂纹转子中刚度变化比△K ,裂纹角 β ,不平衡参数U对系统分叉及浑沌行为的影响。在转速区Ω =2Ωc/3附近 ,当△K较大时 ,会出现分叉及浑沌现象 ,β对这些行为有很大影响。在Ω =Ωc/2附近 ,当△K很大时 ,无论 β为何值 ,将由拟周期通向浑沌。U作为一种外部因素 ,将使系统的非线性行为得到激发或抑制。

Bifurcation and chaos influenced by the ratio △K of stiffness change,crack angle β and unbalance parameter U of a nonlinear cracked rotor in whirl speed are investigated.The system is abundant in periodic,quasiperiodic and chaotic motions when the rotating speed is near 2Ω c/3,and β can affect these behaviors greatly.At the rotating speed of Ω c/2,quasiperiodic responses will bifurcate to chaos.As regards the unbalance parameter U,it doesn't change the property of bifurcation and chaos essentially,and just makes them to be restrained or excited.