不同孔式节流器对圆盘止推气体轴承静特性的影响

The Effect of Different Orifice Restrictor on Static Performance of Externally Pressurized Circular Thrust Gas Bearings

采用保角变换有限元方法计算采用相同供气孔径的不同孔式节流器对静压圆盘止推气体轴承静特性(包括承载力特性、静刚度特性及流量特性)的影响。对承载力和流量特性的分析结果与Kazim ierski的研究结果一致,即:采用相同供气孔径的简单孔式和环形孔式节流器止推轴承,在其他几何参数和工作参数相同的条件下,前者的承载力系数高于后者,但后者的单位载荷气体消耗率要小于前者。对静刚度特性的分析结果表明,同尺寸供气孔径的简单孔式节流器与环形孔式节流器止推轴承,在其他几何参数和工作参数相同的条件下,可以实现的最大静刚度相当,但前者最大静刚度点对应的气膜高度大于后者,因此采用简单孔式节流器时,止推轴承的设计工作点对应的气膜高度可以大一些,这意味着可在一定程度上降低对轴承制造精度的要求。

Influence of different orifice restrictor on static performances of externally pressurized circular thrust gas bearings was calculated by means of conformal transformation FEM, which included load characteristics,flux characteristics and static stiffness characteristics. Under the condition of same orifice diameter and same other geometric parameters and opera- tion parameters,load coefficient of bearing with simple orifice restrictor is bigger than that with inherent orifice restrictor, but power consumption per unit of load is less for the bearing with inherent orifice restrictor than for the bearing with simple orifice restrictor, which is in accordance with the analysis results of Kazimierski. Analysis of static stiffness characteristics indicates that under the condition of same orifice diameter and same other geometric parameters and operation parameters, maximum static stiffness value of bearing with simple orifice restrictor is equal with that with inherent orifice restrictor, but film height corresponding maximum static stiffness point of the bearing with simple orifice restrictor is higher than that with inherent orifice restrictor. It is implied that requirements of manufacture precision for the former may reduce in a certain extent.