为了提高Nanosys-1000非球面曲面光学零件超精密加工机床加工精度, 研究了机床核心部件静压止推轴承内流场分布规律, 进而揭示其承载特性。利用ANSYS/Fluent软件建立对称结构静压止推轴承扇形油垫的仿真模型, 采用层流模式对进油压力为1.3~1.9 MPa、油膜厚度为20~36 μm的油垫流场分布规律与承载特性进行分析。研究结果表明: 油垫内压力在油腔区域比较均匀, 沿封油边呈线性下降; 油膜承载力随油腔压力线性增长, 且在同一进油压力下, 油膜厚度越小, 油膜承载力越大, 进油压力为1.5 MPa时, 油膜厚度从36 μm减小到20 μm, 油腔压力从3.05×105 Pa增加到8.02×105 Pa, 油膜承载力相应地从880 N增加到2 109 N; 同一负载即油膜承载力下, 进油压力越高, 油膜厚度越大, 油膜承载力为1 320 N时, 进油压力从1.3 MPa增加到1.9 MPa, 油膜厚度从26 μm增加到30 μm; 同一油膜厚度下, 进油压力越高, 润滑油流量越大, 油膜厚度为28 μm时, 进油压力从1.3 MPa增加到1.9 MPa, 润滑油流量从0.179 L/min增加到0.231 L/min。相关研究结果在研制的Nanosys-1000非球面曲面超精密加工机床静压止推轴承上得到了验证。

To improve the machining accuracy of Nanosys-1000 ultra-precision machine for aspheric optics, the flow distribution of a hydrostatic thrust bearing which is one of core components in the machine was researched to reveal the characteristics of the bearing．A simulation model of fan-shaped oil pad for a symmetrical structure hydrostatic thrust bearing was created by using ANSYS/Fluent software, and the flow field distribution law and bearing characteristics of the oil pad on a inlet oil pressure of 1.3-1.9 MPa and an oil film thickness of 20-36 μm were analyzed by using a laminar flow model. The results show that the pressure in the oil chamber region is very uniform and it decreases linearly along resistive oil edges. Furthermore, the oil film bearing capacity is linear growth with the oil cavity pressure.Under the same inlet oil pressure, the smaller the oil film thickness is, the greater the oil film bearing capacity is; when inlet oil pressure is 1.5 MPa, the oil film thickness decreases from 36 μm to 20 μm and the oil cavity pressure increases from 3.05×105 Pa to 8.02×105 Pa; accordingly, the oil film bearing capacity increases from 880 N to 2 109 N. Under the same load, the higher the inlet oil pressure is, the larger the oil film thickness is; when the oil film bearing capacity is 1 320 N, the inlet oil pressure increases from 1.3 MPa to 1.9 MPa; accordingly, the oil film thickness increases from 26 μm to 30 μm. Moreover, under the same oil film thickness, the higher the inlet oil pressureis, the larger the oil flow is; when the oil film thickness is 28 μm, the inlet oil pressure increases from 1.3 MPa to 1.9 MPa; accordingly, the oil flow increases from 0.179 L/min to 0.231 L/min. The relative research results have been verified in the hydrostatic thrust bearing of the Nanosys-1 000 ultra-precision machining tool.