可倾瓦滑动轴承—转子系统振动稳定性分析

发布时间：2018-07-12 21:46

本文选题：可倾瓦滑动轴承 + 转子系统　；参考：《华东理工大学》2017年硕士论文

【摘要】：可倾瓦滑动轴承广泛应用于各种高速旋转机械中,轴承的运动状态对旋转机械的稳定性起着至关重要的作用。研究轴承和转子参数对可倾瓦轴承—转子系统稳定性的影响,对于轴承的结构优化设计以及转子系统的故障诊断都具有较为重要的理论意义和工程价值。本文在滑动轴承动态雷诺方程的基础上,基于轴向压力抛物线分布假设,得到简化的一维动态雷诺方程。在充分考虑可倾瓦滑动轴承瓦块摆动以及结构参数的基础上,采用有限差分法对可倾瓦滑动轴承一维动态雷诺方程做了离散处理并用雷诺方程边界条件定解,通过MATLAB进行编程计算,得到油膜力。根据各瓦块相互之间的位置姿态,利用欧拉方法求解轴心轨迹,分析轴颈转速,轴承半径间隙,瓦块数目对稳定性的影响。通过分析发现:轴心涡动幅值和各个瓦块的最大压强随着轴颈转速的提高而增大,并且在靠近极限转速时,最大压强会迅速增大;而减小轴承半径间隙和增加瓦数都能使转子系统的极限转速值增大,但是瓦数增加也会使轴心涡动幅值增加。因此,在设计和安装轴承时,要选择适合的半径间隙及瓦数以适应系统转速和稳定性的要求。结合实际离心式压缩机转子,通过建立其集总参数模型,利用Raccati传递矩阵求解该转子系统的临界转速和不平衡响应,并探讨不同支承参数对临界转速的影响规律,为转子系统的结构优化设计提供参考。
[Abstract]:Tilting pad sliding bearings are widely used in various high speed rotating machinery. The motion state of the bearings plays an important role in the stability of rotating machinery. The study of the influence of bearing and rotor parameters on the stability of tilting bearing rotor system is of great theoretical significance and engineering value for the optimum design of bearing structure and the fault diagnosis of rotor system. Based on the dynamic Reynolds equation of sliding bearing and the assumption of axial pressure parabola distribution, a simplified one-dimensional dynamic Reynolds equation is obtained in this paper. On the basis of fully considering the swinging of tilting pad sliding bearing and the structural parameters, the one-dimensional dynamic Reynolds equation of tilting pad sliding bearing is discretized by the finite difference method and the solution is determined by the Reynolds equation boundary condition. Through MATLAB programming calculation, the oil film force is obtained. According to the position and attitude of each tile, the influence of journal speed, bearing radius clearance and the number of tiles on the stability is analyzed by Euler method. It is found that the axial vortex amplitude and the maximum pressure of each tile increase with the increase of the rotating speed of the shaft neck, and the maximum pressure increases rapidly near the limit speed. The limit rotational speed of the rotor system can be increased by decreasing the radius clearance of the bearing and increasing the number of the bush, but the amplitude of the axial vortex will also be increased by the increase of the number of the bearing. Therefore, in the design and installation of bearings, the appropriate radius clearance and the number of tiles should be selected to meet the system speed and stability requirements. Combined with the actual centrifugal compressor rotor, by establishing its lumped parameter model, the critical speed and unbalance response of the rotor system are solved by Raccati transfer matrix, and the influence of different supporting parameters on the critical speed is discussed. It provides a reference for the structure optimization design of rotor system.
【学位授予单位】：华东理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TH133.31

【参考文献】