气体静压导轨气膜振动的数值模拟

Numerical Study on Vibration Characteristic of Air Film in Aerostatic Lubrication

气体润滑气膜振动现象对超精密加工与测量的精度有重要影响,为了研究气膜振动的成因,本文应用了k-ε湍流模型,对双节流孔的气膜流场压力的振动进行了数值分析.气膜厚度、气膜入口流场条件和双节流孔的间距分别单独调整以分析其对气膜振动的影响.分析结果显示:气膜参数决定了流场的特性,气膜厚度减小将会增大导轨的承载能力;周期性的气膜入口流速将增大气膜的振动;双节流孔的间距增大也会大大增加振动.

The air film vibration has a great effect on the measurement precision directly. In order to study the causes of the air film vibration, the k-ε model is used to simulate the pressure variation of two inlets air film. The air film thickness, the air velocity of throttle pore and the distance of the two inlets are changed respectively to study their effect on the vibration. The results show that： the parameters of the air film change the characteristic of the flow field, less air film thickness can increase the aerostaticbearing capacity, periodical air velocity of the throttle pores can increase the vibration of the air film, and more distance between the two inlets can strengthen the vibration as well.