基于CFD开槽静压气体球轴承轴向承载性能分析

Axial Load Capacity of Hydrostatic Spherical Gas Bearing With Grooves Based on CFD

为提高精密机床主轴支撑的承载能力,增强机床的工作性能,以静压气体球轴承为研究对象,通过开设不同形式的纬线槽和经线槽,运用CFD理论对径向和轴向复合偏心下轴承的轴向承载性能进行了研究,并分析了轴承轴向承载力与纬线槽和经线槽几何尺寸的关系。研究发现:纬线槽可实现轴承间隙内的压力均化作用,降低压力下降速度,改善轴向承载性能;经线槽通过压力均化和动压效应,增大气膜流场压力,提高轴承承载力和刚度;轴承的轴向承载力受纬线槽槽宽和经线槽槽深影响较大,一定范围内增大纬线槽槽宽或经线槽槽深可以较快提高轴向承载力。纬线槽和经线槽的开设形式及几何尺寸对静压气体球轴承轴向承载性能的影响研究为气体轴承的重载应用提供参考。

In order to improve the load capacity of spindle support and enhance the working performance of precision machine tool, the hydrostatic spherical gas bearing was chosen as the research object. The bearings were set up in different forms of latitudinal or longitudinal grooves. The axial load capacity of bearings with radial and axial eccentricity was researched by CFD theory. The relationship between axial load capacity and geometric dimensions of latitudinal and longitudinal grooves was analyzed. It is found that the latitudinal grooves can homogenize the gas pressure in bearing clearance and slow down the speed of pressure reduction to improve axial bearing capacity. Through the pressure homogenization and dynamic pressure effect, the longitudinal grooves can increase the pressure of gas film flow field and improve the load capacity and stiffness of bearing. The axial load capacity of hydrostatic spherical gas bearing is greatly influenced by the width of latitudinal grooves and the depth of longitudinal grooves. Increasing the width of latitudinal grooves or the depth of longitudinal grooves can improve the axial load capacity faster in a certain range. It would provide reference for application of gas bearing in heavy load situations to research the influence of forms and geometric dimensions of the latitudinal and longitudinal grooves on the axial load capacity.