小孔节流静压支承轴承力学性能的数值建模

摘要

To discuss the impact of bearing parameters,including the restrictor size,air film thickness and air supply pressure,on mechanical performance of the orifice restricted aerostatic bearing.Firstly,taking the orifice restricted hydrostatic thrust bearing with cylindrical chamber for an example,carried out a numerical simulation and analyzed in the bearing clearance flow field,in which the orifice size,air chamber size,air supply pressure and air film thickness were taken as the design variables,established an orthogonal array by utilizing the basic principle of orthogonal experimental design,and then took samples through numerical calculation of the bearing clearance flow field to obtain load carrying capacity and stiffness of the bearing;secondly,built an analysis mathematical model for load capacity and stiffness,in which the functions of each parameter and the impact of flow field structure on the mechanical performance were taken into consideration,within the range of design variables based on the radial basis functions model,and the obtained model was proved with sufficient precision through fitting verification;finally,analyzed the impact of orifice size and air chamber size on load capacity and stiffness of the bearing,which provided a reference for engineering design.%为了讨论小孔节流空气静压支承轴承的节流器尺寸,气膜厚度与供气压等轴承参数对轴承力学性能的影响.针对圆柱腔小孔节流静压支承止推轴承,首先进行了轴承间隙流场的数值仿真与分析,其中以小孑尺寸,气腔尺寸,供气压及气膜厚为设计变量,利用正交实验设计的基本原理构造正交表,通过对轴承间隙流场的数值计算进行采样以获取轴承的承载力与刚度;其次在设计变量范围内基于径向基神经网络模型建立承载力与刚度的分析数学模型,在该分析模型中全面考虑了各轴承参数的作用,同时考虑了轴承间隙的流场结构对力学性能的影响,得到的模型经过拟合校验以证明具有足够的精度;最后基于该分析模型讨论了小孔与气腔尺寸对轴承承载力与刚度的影响,为工程设计提供了参考.