环形多孔节流空气静压轴承气膜流场分析

为提高空气静压轴承工作的稳定性，设计一种环形多孔节流空气静压轴承，建立其物理模型，并采用大涡模拟方法对轴承节流孔出口处附近计算区域的气膜流场进行分析。结果表明：空气静压轴承气膜压力在节流孔的出口附近气膜间隙上出现分离，但在远离节流孔的出口气膜压力曲线是重合的；节流孔数为9时轴承节流孔出口处的最大压降幅度为节流孔数为1时的26%左右，最大速度突升幅度为节流孔数为1时的43%左右，表明增加节流孔的孔数可以显著减小节流孔的出口附近压力的突降、速度的突升，提高轴承工作稳定性；在空气静压轴承工作过程中，节流孔出口处附近压力和速度的突变会产生微振动现象，而采用环形多孔节流可显著降低微振动现象。

Analysis on Flow Field of Aerostatic Bearing with Annular Multi hole Restrictor

In order to improve the working stability of aerostatic bearing,an annular multi hole restrictor aerostatic bearing was designed,its physical model was established,and the large eddy simulation method was used to analyze the air film flow field near the outlet of the orifice.The results show that the gas film pressure of the aerostatic bearing is separated in the gas film clearance near the outlet of the orifice,however the gas film pressure curve is coincident far from the outlet of the orifice.The maximum pressure drop of the bearing with 9 orifices is about 26% of that with 1 orifice,and the maximum speed increase is about 43% of that with 1 orifice,which shows that increasing the number of orifices can significantly reduce the sudden drop of pressure and speed near the outlet of small orifice,and improve the working stability of bearing.During the aerostatic bearing working,the sudden change of pressure and speed near the outlet of the orifice can cause micro vibration,and the use of annular multi hole restrictor can significantly reduce the micro vibration.