多叶动压气体滑动轴承静态特性的有限差分算法

多叶动压气体滑动轴承因其结构简单、摩擦阻力低、旋转精度高和无环境污染等优点，在高速离心分离机、空气压缩机和透平膨胀机等旋转机械中应用广泛。为探究多叶动压气体滑动轴承的静态性能，通过数学变换将三叶动压轴承的气体润滑Reynolds方程转化为标准偏微分方程形式，利用有限差分法和超松弛迭代法进行数值求解，研究气膜厚度和气膜压力分布、承载力、摩擦因数和质量流量等静态性能，随偏心率、预负荷系数、轴承数、长径比及瓦块分布位置的变化规律。结果表明：三叶轴承的承载力和轴颈表面摩擦因数随偏心率和长径比的增加而增加，而偏位角和质量流量随偏心率和预负荷系数的增加则呈现出相反的变化趋势；随着轴承数和预负荷系数的增大，承载力和摩擦因数显著提高，偏位角和质量流量则逐渐减小；瓦块分布位置对三叶动压气体滑动轴承的静态性能影响显著，其中瓦上承载方式的承载力、偏位角和质量流量明显高于瓦间承载方式。

A Finite Difference Algorithm for Solving the Static Characteristics of Multi-leaf Aerodynamic Bearing

Multi-leaf hydrodynamic gas journal bearing is widely used in high-speed centrifugal separator,air compressors,turboexpander and other rotating machinery due to its simple structure,low friction resistance and pollution-free.In order to explore the static performance of multi-leaf hydrodynamic gas journal bearing,the Reynolds equation of three-leaf hydrodynamic bearing was transformed into the standard partial differential equation through mathematical transformation,and was solved by finite difference method and over-relaxation iterative method.The variation of static performance such as gas film thickness and pressure distribution,load carrying capacity,friction coefficient and mass flow rate with eccentricity ratio,preload factor,bearing number,length-to-diameter ratio and pad distribution position was studied.The results show that the load carrying capacity and friction coefficient of the journal surface of three-leaf gas bearing increase with the increase of eccentricity ratio and length-to-diameter ratio,while the attitude angle and mass flow rate exhibit opposite trend with the increase of eccentricity ratio and preload factor.As the bearing number and preload factor increase,the bearing capacity and friction coefficient significantly increase,while the attitude angle and mass flow rate gradually decrease.The distribution position of tiles has a significant impact on the static performance of three-leaf gas bearing,the load carrying capacity,mass flow rate and attitude angle of load on pad are significantly higher than those of load between pad.