气流参数对多孔质空气静压轴承静态特性及性能影响研究

Influence of flow parameters on static characteristics of porous aerostatic bearing

空气静压轴承在精密机床和计量设备等制造业领域应用广泛.多孔质空气静压轴承是一种特殊类型的空气静压轴承,其由于使用了多孔质材料,因此更加稳定和坚固.目前针对这类轴承有关气流参数对轴承静态特性及性能影响的研究还较为欠缺.为此,本文提出了一个数学模型用于模拟多孔质空气静压推力轴承的静态特性,包括承载能力、刚度及质量流率等.通过使用基于Navier-Stokes方程的计算,对轴承内部的压力分布进行了分析.随后,研究了对轴承静态特性可能产生影响的相关气流参数及其影响情况.研究结果表明,轴承气膜层厚度的增加会导致轴承承载能力和刚度的下降,但增加多孔质层的厚度可以提高轴承刚度.此外,增加气膜层厚度会使得进入轴承的空气质量流率得以提升.这些结果可用于帮助设计更为高效且能够承担更高负载的多孔质空气静压轴承.

There is a wide variety of applications of aerostatic bearings in manufacturing such as those in precision machine tools and metrology equipment.As a specific type of aerostatic bearings,porous aerostatic bearings are more stable and stronger due to the use of porous materials.There is still not much research on the static characteristics influenced by flow-related parameters.In this paper,a mathematic model is proposed to simulate the static properties of porous aerostatic thrust bearings,including load-carrying capacity,mass flow rate and stiffness.The pressure distribution inside the bearing is analyzed by calculation based on Navier-Stokes equations.The flow factors and their effect on bearing static properties are then investigated.The findings indicate that,an increase in film thickness of the bearing shall cause load-carrying capacity decrease and also stiffness decrease.However,by increasing the thickness of porous layer the stiffness of the bearing can be effectively increased.In addition,the increased film thickness shall result in an increased mass flow rate into the bearing.These findings can be used to help design porous aerostatic bearings that are more efficient and able to handle higher loads.