转定子静态不对中条件下碰摩故障仿真

本资料包含pdf文件1个，下载需要1积分

In this paper, taking a flexible rotor system with single span and two discs as the research object, the finite element model of the rotor-bearing system is established. The stator is simplified as a group of equispaced points along the circumfer- ence and the rotor as a point based on contact dynamics theory. The rotor-stator rub-impact is simulated using multiple point- point contact elements. The separation and contact of rotor and stator are determined by the change of cylindrical gap, and the rotor and stator model are coupled by nonlinear rub-contact force. By adopting the augmented Lagrangian method to deal with constraint conditions of the contact, and coulomb friction model to simulate rotor-stator frictional characteristics, the responses of the rotor system with rubbing are analyzed. The effects of rotation speed, equivalent collision stiffness and damping, and friction coefficient on rub-impact forces are discussed under static rotor-stator misalignment conditions. The results show that there may be different types of rub-impact （local and full） and transient impact forces under different rotation speeds. Equiva- lent collision stiffness has the greatest effects on the normal rub-impact force, the amount of misalignment affects mainly the transient impact force and does not affect the steady rub-impact force, equivalent collision damping and friction coefficient have some influence on normal rub-impact force.以一个单跨双盘柔性转子系统为研究对象，首先建立转子系统有限元模型，将定子简化为一个沿圆周方向均布的点集，转子考虑为一个点，通过建立多个点一点接触单元来模拟转定子碰摩故障，通过检测点一点接触单元之间的间隙来确定转子的分离及接触，进而通过碰摩力耦合转定子模型，采用增广的拉格朗日方法来处理接触约束条件，用库仑摩擦模型来模拟转定子之间摩擦。考虑在转定子不对中情况下，转速、转定子当量碰撞刚度、当量碰撞阻尼和摩擦系数对碰摩力的影响。研究结果表明在不同转速下，可能存在不同的碰摩形式（局部碰摩和整周碰摩）及瞬时冲击力；当量碰撞刚度对法向碰摩力影响最大，不对中量主要影响瞬时冲击力，对稳态碰摩力影响不大，当量碰撞阻尼和摩擦系数对法向碰摩力有一定影响。