空气静压轴承微振动形成机理分析  

Formation mechanism of micro-vibration in aerostatic bearings

作　　者：裴浩[1] 龙威[1] 杨绍华[1] 公玲[1] PEI Hao;LONG Wei;YANG Shaohua;GONG Ling(College of Mechanical and Electrical Engineering, Kunming University of Science and Technology, Kunming 650504, China)

机构地区：[1]昆明理工大学机电工程学院,昆明650504

出　　处：《振动与冲击》2018年第5期71-78,共8页Journal of Vibration and Shock

基　　金：国家自然科学基金资助项目(51305185);清华大学摩擦学国家重点实验室开放基金资助项目(SKLTKF16B02)

摘　　要：为了进一步提高气体静压轴承的工作精度和稳定性,根据冲击射流理论对气体轴承进气孔区域气体流动状态和传热特性进行分析,将供气孔-气膜入口区域流场划分成四个部分,即:自由射流区、滞止区、过渡区、出口壁面射流区。基于二维平面流函数和大涡模拟方法,确定了气膜微振动的产生源于进口区域流场内存在三种典型气旋形式,即:供气孔附近的主气旋,气腔内部的次气旋和气膜入口的附加气旋。利用气体分子运动论结合表面-界面物理方法,明确了三种气旋的产生机理,发展规律和变化趋势,同时进一步研究了不同工况下气膜内压力的变化与四个区位置以及范围之间的关系,并对气膜内压力波动的位置及强度进行分析。最后,通过搭建试验台测试轴承气膜的振动幅值变化和频率响应函数,不仅验证了三类气旋的存在及其分布特征,有力证明了供气孔入口区域流场分区设想的合理性;通过数值计算和实验数据相结合,还进一步给出了影响气膜微振动强度的影响因素及其规律。In order to further improve working accuracy and stability of an air bearing,gas flow state and heat transfer characteristics of its inlet region were analyzed according to the impinging jet theory,the flow field of gas supply hole was divided into four parts including free jet zone,stagnation one,transition one and outlet wall jet one.Based on the two-dimensional planar flow function and the large eddy simulation method,it was determined that micro-vibration of gas film is caused due to three typical cyclonic forms in the inlet region including main cyclone near gas supply hole,sub-cyclone inside gas cavity and additional one at gas film inlet.The evolution mechanism,development law and varying trend of the three cyclones were clarified with the gas molecular motion theory combined with the surface-interface physical method.At the same time,relations among pressure change in gas film,4zones’positions and ranges were studied,location and intensity of pressure fluctuation in gas film were analyzed.At last,vibration amplitude variation and frequency response function of gas film were measured on a test rig to verify the existence and distribution of the three cyclones,and the reasonableness of gas supply hole flow field partition.The influence factors and laws of gas film micro-vibration intensity were also given with the combination of numerical computation and test data.

关 键 词：气体轴承 微振动 气旋 冲击射流 大涡模拟 

分 类 号：H133.36[语言文字—汉语]