基于正交试验的液体动静压球轴承动态特性数值分析

Numerical Analysis of Dynamic Characteristics of Spherical Hybrid Sliding Bearing Based on Orthogonal Experiment

摘要: 偏心率是衡量轴承性能的关键参数，它描述了轴承内部润滑膜的均匀性和稳定性，为研究轴承工作参数对轴承的偏心率影响，本文以小孔节流的液体动静压球轴承为研究对象，根据流量连续条件求解出油腔压力，使用有限差分法离散化Reynolds方程并通过松弛迭代法求解得到无量纲油膜压力，进而得到轴承承载力，基于液体动静压球轴承转子系统动力学模型并采用欧拉算法计算得到轴承平衡时轴心的位置，从而求出轴承的偏心率。采用正交试验方法，探究了转速、供油压力、油膜厚度对液体动静压球轴承的偏心率的影响，对试验结果进行极差分析和方差分析可得：试验条件下，轴承的工作参数对偏心率的影响从大到小排序依次为：供油压力、转速、油膜厚度，并确定出供油压力为2.5 Mpa、油膜厚度为30 μm、转速为2500 r/min时，液体动静压球轴承的偏心率最小。

Abstract: Eccentricity is a key parameter to measure the performance of bearings, which describes the uni-formity and stability of the lubrication film inside the bearings. In order to study the influence of bearing operating parameters on the eccentricity of the bearings, this paper takes the spherical hybrid sliding bearings with small holes throttling as the research object, solves the oil cavity pres-sure according to the condition of flow continuity, discretizes Reynolds’ equations by using the finite difference method, and obtains the dimensionless oil film pressure by solving the method of itera-tive relaxation, and then obtains the bearing load carrying capacity. Based on the spherical hybrid sliding bearing rotor system dynamics model and Euler’s algorithm, the position of the axial center when the bearing is in equilibrium is obtained, so as to find out the eccentricity of the bearing. The orthogonal test method was used to investigate the effects of rotational speed, oil supply pressure and oil film thickness on the eccentricity of the spherical hybrid sliding bearings, and the extreme deviation analysis and variance analysis of the test results showed that under the test conditions, the working parameters of the bearings had the following effects on the eccentricity in descending order: The oil supply pressure, rotational speed, and the thickness of the oil film, and it was deter-mined that the oil supply pressure was 2.5 Mpa, and the thickness of the oil film was 30 μm, When the rotational speed is 2500 r/min, the eccentricity of the spherical hybrid sliding bearing is mini-mized.