非线性摩擦力对碰摩转子-轴承系统混沌运动的影响

在考虑轴承油膜力和非线性摩擦力的基础上,构造了具有碰摩故障转子-轴承系统的动力学模型,对碰摩故障转子在运行过程中的非线性行为进行了研究,并分析了转静件间相对速度影响因数对转子分岔与混沌运动的影响·发现随着速度影响因数的增加,在亚临界转速区,拟周期和混沌运动区域增大;在超临界转速区,混沌运动区域减小,碰摩力的作用效果增大,拟周期运动逐渐演变为周期3运动·该结果为转子-轴承系统的故障诊断提供了依据和参考·

Effects of Nonlinear Friction Force on Chaotic Motion of Rotor-bearing System at Rub-impact Faults

Considering the strong nonlinear oil-film force and influence of nonlinear friction force, a dynamic model was set up for the rotor-bearing system at rub-impact faults. The nonlinear dynamic behaviors in running were investigated widely on a basis of modern nonlinear dynamics and rotor dynamics theory with the influence of the coefficient of relative speed between rotary and stationary parts on the bifurcation and chaotic motion of the system discussed. Lots of nonlinear phenomena investigated revealed that within the subcritical speed range both the quasi-period and chaotic motion regions increase with the increase of relative speed coefficient. However, within the supercritical speed range, the chaotic motion region decreases, but the rub-impact forces increase and the quasi-period motions become gradually the period 3 ones. These provide a theoretic basis reference for the failure diagnosis to the rotor-bearing systems at rub-impact faults.