变截面多轴段双刚度转子运动失稳研究及验证

Rotor motion instability research and verification based on variable cross-section multi-axis segment and double stiffness

针对单截面双刚度转子失稳分析原理与局限,对变截面多轴段双刚度转子提出一种可行的双向刚度差异系数的计算方法,同时考虑因滚动轴承在高转速、低负载、大黏度情况下接触刚度与油膜刚度相当而导致随转子转速增大,其综合径向支承刚度下降对失稳区的影响,采用集中质量法将变截面多轴段双刚度转子简化为多圆盘转子系统进行运动失稳分析,求出其临界转速及对应的失稳区,并与某型航空发动机燃烧室甩油盘试验器高速电机振动测试结果进行对比,情况基本吻合。

A feasible two-way stiffness difference coefficient calculation method was proposed aiming at the variable crosssection multi-segment double stiffness rotor based on the instability analysis principle and limitations of the single cross-section double stiffness rotor. At the same time, the contact stiffness and oil film stiffness of rolling bearing was in the same order in the condition of high speed, low load and large viscosity. Therefore, the instability area would be influenced with the increasing rotor speed combined the declined radial support stiffness. The motion instability analysis was performed using the lumped mass method to simplify the variable cross-section multi-segment double stiffness rotor into multi-disc rotor system. The critical speed and the corresponding instability area could be solved out. And the comparison analysis of an aero-engine combustor jilt oil pan tester high-speed motor vibration test was performed to obtain the better validation. The method had a certain engineering significance.