摘要
采用非线性稳态短轴承模型,以多自由度转子系统为研究对象,运用模态降阶和变步长的Newmark积分方法,对油膜振荡的各种影响因素、轴颈的涡动轨迹、频谱进行了计算分析.计算结果表明,增加外阻尼可以消除复杂的轴心轨迹以及降低半频涡动的峰值.在理论分析的基础上提出了通过增加电磁阻尼在线消除油膜振荡的方法.在一个带有六圆盘的实验台上进行了实验研究,给被动式电磁阻尼器施加电流,油膜振荡消除,关掉电源,油膜振荡又出现.阻尼器安装在轴的外伸端,无需改变机器结构,且不影响机器的正常运行.
The nonlinear dynamic characteristics (including the trajectories of bearings, frequency spectrum and the factors inducing to oil whip) of a multi-freedom flexible rotor supported on oil journal bearings were numerically studied by variable step-size Newmark integration. The nonlinear oil film forces of the bearings were modeled based on steady short bearing theory. The simulation analysis shows that the complex trajectories disappear and the amplitude of the half frequency vibration distinctly decreases by adding external damping. So experiments were carried out to clarify this phenomenon and demonstrate the feasibility. A test rotor with six disks was equipped on its free end with a passive electromagnetic damper, which worked without contact and with DC current. The power of the damper was turned on when the oil whip of the rotor occurred. It was observed that when the damper was turn on, the complex trajectories of the journal motion disappeared and the rotor-bearing system became stable; when the damper was turned off, the oil whip occurred again.
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2005年第2期238-241,共4页
Journal of Zhejiang University：Engineering Science
基金
国家自然科学基金资助项目(50375140).
