载荷分布对空气静压轴承振动特性的实验

针对空气静压轴承涡激振动问题，以圆盘型小孔节流空气静压轴承为研究对象，基于涡流激振原理和振荡流体力学理论，分析了气膜的动态特性和流体激振稳定性；采用平面流函数分析了三维气旋涡量分布特征；最后利用实验测试及理论研究相结合的方法分析了载荷分布对气浮轴承微振动特性的影响规律。研究发现：空气静压轴承的微振动本质上是气膜流场内的非定常流动引起的涡旋和壁面之间的耦合作用，即压力脉动和涡量分布决定的。轴承表面的载荷分布情况直接决定气膜高度方向的压力梯度和能量转化趋势；供气压力和气膜厚度的改变直接影响气膜内总能量输入和流动过程中能量损耗及转化形式。

Experiment of load distribution on micro-vibration characteristics of aerostatic bearings

To solve the problem of vortex-induced vibration of aerostatic bearings, the disc small hole throttled aerostatic pressure bearing is taken as the research object. Based on the principle of vortex excitation and the theory of oscillatory fluid mechanics, the dynamic characteristics and fluid induced vibration stability of gas films are examined. Analysis of the characteristics of three-dimensional cyclonic vorticity distribution is then conducted using the plane flow function. Finally, the influence of offset load on the micro-vibration characteristics of air bearings is explored by means of numerical simulation and experimental tests. The study reveals that the micro vibration of aerostatic bearings is essentially the coupling between the vortex and the wall caused by unstable flow in the film flow field. Specifically, it is determined by pressure pulsation and vorticity distribution. Load distribution on the bearing surface directly determines the pressure gradient and energy conversion trend in the direction of the film height. The change of gas supply pressure and film thickness directly affects energy loss and conversion form in the process of total energy input and flow in the gas film.