针对微小间隙下空气静压轴承内部气体的稀薄效应问题,通过将体现稀薄效应的流量因子引入雷诺方程中,推导出体现可压缩气体稀薄效应的雷诺方程,运用有限差分法离散方程,通过MATLAB软件分析稀薄效应下轴承内部压强分布,并对轴承承载力和刚度变化进行研究,最后通过试验对得出的结论进行间接验证。结果表明,在气膜间隙8~10μm之间,考虑稀薄效应中流量因子的情况下得到的轴承刚度值与试验测量值比较接近,在量值上相差大约为20%左右,这为微尺度下轴承性能的研究提供一定的理论依据。
For the problem of gas rarefied effect inside the aerostatic bearing in condition of micro clearance,the Reynolds equation suitable for compressible gas in the rarefied effect was deduced through introducing flow factor of the rarefied effect to the Reynolds equation. The Reynolds equation was dissociated by using the finite element method,pressure distribution in the bearing under the rarefied effect were analyzed by the software MATLAB,the influence rule of rarefied effect to the bearing performance capacity and stiffness was studied,which was verified by experiment indirectly. The results showed that the stiffness of bearing in condition of considering the flow factor was close to the stiffness tested by experiment when the gas clearance was 8 ~ 10 μm.The value of analysis was 20% less than the experiment,which provided a theoretical basis to the research of the performance of bearings in micro-scale.