摘要
为提升空气静压轴承对动载荷的抵抗能力,针对气膜-被支承件系统的位移阻抗性能进行研究,讨论轴承参数对位移阻抗的影响。首先采用数值仿真并结合动网格技术讨论轴承气膜的刚度、阻尼特性;然后对于气膜-被支承件系统的位移阻抗性能进行研究,基于径向基神经网络模型构建近似模型,讨论激励频率、孔径、气膜厚度、供气压力对位移阻抗的影响特性;最后基于优化设计,在不同给定激励频率下获取使轴承位移阻抗最大的参数组合,并就优化结果进一步对力学性能进行了讨论。研究表明:位移阻抗随频率增加而增加,其余参数对其具有非单调影响;在小气膜厚度下,位移阻抗更大,然而单纯增减供气压不能提升位移阻抗,即不能通过单纯调整供气压提升气膜抵抗动载荷的能力;由于位移阻抗直接反映气膜对动载荷的抵抗能力,因此基于优化设计提升位移阻抗,可以有效增强气膜对动载荷的抵抗能力,进一步提升轴承的动力学性能。相关优化建模流程可为以动力学性能提升为目的的轴承设计提供参考。
To improve the dynamic load resistance capability of the aerostatic bearing,the displacement impedance performance of the air film-floating facility system was studied,and the influence mechanism of bearing parameters on displacement impedance was discussed.The numerical simulation and dynamic mesh method were adopted to discuss the air film stiffness and damping characteristics.The displacement impedance performance of the air film-floating facility system was investigated,and the influence characteristics of excitation-frequency,orifice diameter,air film thickness and air supply pressure on the displacement impedance were discussed.The optimization was conducted under a series of excitation frequencies to achieve the bearing parameters with the maximum displacement impedance,and the mechanical performance was further discussed based on the optimization.The results indicate that the displacement impedance increases with increase of the excitation frequency,and other parameters have non-monotonic influences on the displacement impedance.The higher displacement impedance can be achieved with a small air film thickness,however,only by increasing or decreasing the air supply pressure cannot enhance the displacement impedance,that is,the dynamic load resistance capability of the air film cannot be improved by only adjusting the supply pressure.Because the displacement impedance directly reflects the dynamic load resistance capability of the air film,the improvement of the displacement impedance through design optimization can certainly enhance the dynamic load resistance capability of the air film,improve the dynamic performance of the aerostatic bearing.The optimization modelling procedure can provide a reference for the aerostatic bearing design to enhance the dynamic performances.
作者
李一飞
尹益辉
LI Yifei;YIN Yihui(School of Civil and Transportation Engineering,Qinghai Minzu University,Xining Qinghai 810007,China;Institute of Systems Engineering,China Academy of Engineering Physics,Mianyang Sichuan 621900,China)
出处
《润滑与密封》
CAS
CSCD
北大核心
2022年第9期50-55,共6页
Lubrication Engineering
基金
青海省二〇二二年基础研究计划项目(2022-ZJ-757)。
关键词
空气静压轴承
位移阻抗
动力学性能
静力学性能
aerostatic bearing
displacement impedance
dynamic performances
static properties
