高速静压气体轴承承载特性的研究

发布时间：2018-12-27 07:41

【摘要】：静压气体轴承由于具有摩擦阻力小、运转速度快、工作精度高及工作范围广等优点已经在精密加工、微电子和航空航天等领域得到广泛应用。但在工程应用中人们也遇到一些问题，例如，在超高转速下，尤其在转速超过每分钟20万转时，因为受到气动力的影响、转子动不平衡等干扰，转子极易出现涡动失稳，导致轴承会产生很严重的磨损甚至“卡死”现象，因此，如何提高承载能力和稳定性对静压气体轴承的推广应用有重要意义。然而，传统的静压气体轴承静动态性能的推导，往往在需要做出很多假设条件之后对雷诺方程进行二维简化求解，单独计算静压效应和动压效应，而后将两者进行线性叠加，不能精确反映润滑气膜内的三维流动。因此，本文利用计算流体力学软件FLUENT，从研究静压气体轴承内部的流场入手，将静压气体轴承承载特性和节流特性作了详细的分析。本文的研究工作大体上分为四个部分，首先，研究了节流孔直径、气膜厚度对静压气体轴承承载特性的影响。其次，对环面节流和小孔节流两种节流方式静压气体轴承承载特性做了对比研究，并对静态仿真值做了实验验证。再次，以新型小孔节流器和传统小孔节流器的对比为主线，对涡动状态下的静压圆柱气体轴承动态特性进行了分析。最后，以三种节流方式为研究对象，分析了转子涡动对静压气体轴承节流特性的影响。本文的研究成果丰富了气体轴承的设计、制造方法，，为今后设计新型静压气体轴承提供了一些指导，对从事此方面研究工作的人员具有一定的参考价值。
[Abstract]:Hydrostatic gas bearing has been widely used in precision machining, microelectronics, aerospace and other fields because of its advantages of low friction resistance, fast running speed, high working precision and wide range of work. However, in engineering applications, people also encounter some problems. For example, under ultra-high speed, especially when the rotational speed exceeds 200000 revolutions per minute, the rotor is prone to vortex instability due to the influence of aerodynamic force and the disturbance of rotor dynamic imbalance. So, how to improve the bearing capacity and stability is of great significance to the popularization and application of hydrostatic gas bearings. However, the traditional derivation of static and dynamic performance of hydrostatic gas bearings is usually based on the simplified solution of Reynolds equation after many assumptions are made, and the static pressure effect and dynamic pressure effect are calculated separately, and then the two equations are superposed linearly. Cannot accurately reflect the three-dimensional flow in the lubricating film. Therefore, in this paper, the bearing and throttling characteristics of hydrostatic gas bearing are analyzed in detail by using the computational fluid dynamics software FLUENT, to study the flow field inside the hydrostatic gas bearing. The research work in this paper is divided into four parts. Firstly, the influence of orifice diameter and film thickness on the bearing characteristics of hydrostatic gas bearing is studied. Secondly, the bearing characteristics of hydrostatic gas bearing with toroidal throttling and orifice throttling are compared and verified by experiments. Thirdly, the dynamic characteristics of the hydrostatic cylindrical gas bearing under the vortex state are analyzed by comparing the new orifice throttle and the traditional orifice throttle. Finally, the effect of rotor vortex on throttling characteristics of hydrostatic gas bearing is analyzed. The research results in this paper enrich the design and manufacturing methods of gas bearings, and provide some guidance for the design of new type hydrostatic gas bearings in the future.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TH133.36

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