椭圆轴承与圆轴承动力特性CFD数值分析

滑动轴承动力特性对旋转机械转子稳定性有着重要影响。将CFD动网格技术应用于椭圆轴承与圆轴承动力特性求解。在验证滑动轴承CFD动力特性求解模型准确性的基础上,建立基于CFD动网格技术的椭圆轴承动力特性求解模型,分析椭圆度、偏心率以及转速等因素对滑动轴承动力特性影响,比较分析椭圆轴承与圆轴承动力特性之间的差异。研究表明,椭圆轴承与圆轴承的承载力与刚度阻尼系数随着偏心率、转速的增加而增大;与圆轴承相比,椭圆轴承两个油楔形成两个流体动压区有效的增大轴承的阻尼,滑动轴承增加椭圆度可提高转子稳定性。

CFDNumericalAnalysisforDynamicCharacteristicsof EllipticalBearingsandCylindricalBearings

The dynamic characteristics of bearings have important effects on stability of the rotating machinery rotor. The computational fluid dynamics (CFD) dynamic mesh technology was applied to solve elliptical bearing and cylinder bearing dynamic characteristics. On the basis of verify the accuracy of the journal bearing dynamic characteristic of CFD model, this paper set up the dynamic characteristics of elliptical bearing and cylinder bearing CFD models based on dynamic mesh technology, analyzed the effects on the journal bearing dynamic characteristics caused by ellipticity, eccentricity and rotational speed, compared dynamic characteristic differences between the elliptical bearing and cylinder bearing. The results prove that with the increasing of the eccentricity and rotational speed, the dynamic characteristics increase. Compared with the cylinder bearing, elliptical bearing that has two oil wedges generates two hydrodynamic lubrication districts, it increases the damping of the bearing effectively, Increasing the ellipticity of bearing can improve the stability of the rotor.