基于流固耦合气体轴承-转子系统的动态特性分析  

Dynamic Characteristics Analysis of Gas-Bearing Rotor System Based on Fluid-Structure Coupling

作　　者：马海龙 马文琦 郑少林 秦雨彬 MA Hailong;MA Wenqi;ZHENG Shaolin;QIN Yubin(Naval Architecture and Ocean Engineering College,Dalian Maritime University,Dalian Liaoning 116026,China)

机构地区：[1]大连海事大学船舶与海洋工程学院,辽宁大连116026

出　　处：《润滑与密封》2024年第6期65-71,共7页Lubrication Engineering

基　　金：国家自然科学基金项目(51075048,51875586);黑龙江省自然科学基金重点项目(ZD2021E005)。

摘　　要：机床切削过程中所受的切削力可假设为稳态力和动态扰动力的合力,为探究以气体轴承作为支承的电主轴系统的动态特性,以正弦波作为动态扰动加载形式,提出采用简谐激励法与双向流固耦合数值模拟相结合的方法对气体轴承-转子系统的简化模型进行动态特性研究;对动刚度和阻尼系数进行辨识,并通过模态分析获得转子不同稳态力下系统振型及固有频率变化规律。研究结果表明:随稳态力的增加,下径向轴承的K_(yy)增长速率大于K_(xx),而交叉刚度和交叉阻尼均几乎不变;下径向轴承的主刚度大于交叉刚度,主阻尼大于交叉阻尼;当稳态力为50~200 N时,转子下端y向偏移均随动态扰动力频率的增加呈现先增大后减小的趋势;系统的共振频率随稳态力的增大而增大。The cutting force suffered by the machine tool in the cutting process can be assumed to be the combined force of the steady state force and the dynamic disturbing force.In order to investigate the dynamic characteristics of electric spindle system supported by gas bearings,sine wave was used as dynamic disturbance loading form,and the dynamic characteristics of a simplified model of a gas bearing rotor system were studied by combining the harmonic excitation method with the bidirectional fluid-structure coupling numerical simulation.The dynamic stiffness and damping coefficients were identified.Through modal analysis,the system vibration modes and natural frequencies of the rotor under different steady-state forces were obtained.The results show that with the increase of steady-state force,the growth rate of K_(yy) of the lower radial bearing is greater than that of K_(xx),while the cross stiffness and cross damping are almost unchanged.The main stiffness of the lower radial bearing is greater than the cross stiffness,and the main damping is greater than the cross damping.When the steady-state force ranges from 50 N to 200 N,the y-shift at the lower end of the rotor first increases and then decreases with the increase of dynamic disturbance frequency.The resonance frequency of the system increases with the increase of the steady-state force.

关 键 词：气体轴承-转子系统 流固耦合 动态特性 模态分析 

分 类 号：TH133.3[机械工程—机械制造及自动化]