空气静压轴颈轴承力学性能的分析优化  

Design Optimization of the Mechanical Performances of theAerostatic Journal Bearing

作　　者：李一飞 黄纬萍 桑冉 LI Yifei;HUANG Weiping;SANG Ran(School of Civil and Transportation Engineering,Qinghai Minzu University,Xining Qinghai 810007,China)

机构地区：[1]青海民族大学土木与交通工程学院,青海西宁810007

出　　处：《润滑与密封》2024年第7期67-73,共7页Lubrication Engineering

基　　金：青海省二〇二二年基础研究计划项目(2022-ZJ-757)。

摘　　要：为提升小孔节流空气静压轴颈轴承的静、动力学性能,针对轴承间隙的流场特性与轴承的承载力、位移阻抗性能进行分析与优化。采用数值仿真方法分析轴承间隙的流场特性,并在参数设计中消除了气膜流场中的超音速区,以避免微振动;分析轴承气膜的刚度、阻尼性能,并采用ESA-CFD(Engineering Simplification Algorithm-Computational Fluid Dynamics)方法计算轴承振动系统的位移阻抗。结果表明,气膜压力自小孔至外边界逐渐衰减,小孔出口出现激波可导致漩涡流动并引起微振动,微振动形成机制与止推轴承相似。建立优化设计数学模型,以轴颈轴承的位移阻抗、承载力为设计目标,并消除轴承微振动,其中考虑多组偏心率与激励频率的组合。通过优化设计,提升了轴颈轴承的力学性能,相关优化、分析过程可为工程应用中空气静压轴颈轴承的设计提供参考。To improve both the static and the dynamic performances of the aerostatic journal bearing,the flow characteristics in the bearing clearance,the displacement impedance,as well as the load carrying capacity were analyzed and optimized.The flow structures in the bearing clearance were analyzed by numerical simulation method.The supersonic region in the flow field of the air film was eliminated to suppress the micro-vibration.The stiffness and damping of the bearing air film were calculated,and the displacement impedance was further achieved based on the Engineering Simplification Algorithm-Computational Fluid Dynamics method.The influences of bearing parameters on the displacement impedance were discussed.It is found that the pressure in the air film decreases from the orifice to the outlet of the air film,and the formation of the shock waves at the outlet of the orifice can induce the vortex flow and then cause the occurrence of the micro-vibration.The formation mechanism of the micro-vibration is similar with that of the thrust bearing.The mathematic model for optimization was established,the displacement impedance and the load carrying capacity were both considered as design objectives,and the elimination of the micro-vibration was also considered.Several cases with different eccentricity ratio and excitation frequency were discussed.Through optimization,the mechanical performances of the journal bearing are improved,and the optimization and analysis process can provide a reference for engineering application of design of the aerostatic journal bearing.

关 键 词：空气静压轴颈轴承 微振动 自激振动 位移阻抗 漩涡流动 

分 类 号：TH133[机械工程—机械制造及自动化]