摘要
研究发现小孔节流器导向锥角也是影响空气静压轴承动静态性能的重要因素之一,且导向锥角大小在加工中易于控制。为揭示导向锥角的大小对轴承动静态性能的影响规律,通过建立空气静压止推轴承节流器理论模型,利用FLUENT软件,对不同导向锥角节流器出口的压力分布和气腔内涡核分布进行有限元模拟;结合DOE仿真实验,获得了不同导向锥角下轴承的静态特性曲线。结果表明:减小节流器导向锥角,可以减缓节流孔出口压力骤降,气腔内涡核数量减少;随着导向锥角的增大,轴承的承载力和质量流量减小,而轴承刚度在小幅度增加后趋于一致。因此,使用小导向锥角的节流器可有效地提高轴承的稳定性和承载力。
It is found that the angle of guide cone of orifice throttles is one of the important factors affecting the static and dynamic performance of aerostatic bearing,and the size of guide cone angle is easy to control in machining.To reveal the influence law of the size of guide angle on bearing dynamic and static performance,the theoretical model of the orifice throttling areostatic thrust bearing was established,and the pressure distribution around throttle's outlet and the vortex core distribution in the air cavity at different orienting cone angle throttles were studied by the finite element simulation based on FLUENT software.By utilizing the DOE simulation experiment,the static characteristic curve of bearing at different guiding cone angle was obtained.The results show that small angle of the guide cone can slow down the pressure drop around the outlet of throttle hole, reduce the number of vortex cores in the air cavity.With the increasing of guide cone angle,the load capacity and mass flow are decreased,while stiffness curves tend to be consistent after a small increase.Therefore,the use of small guide Angle throttle can effectively improve the stability and load capacity of the bearing.
引文
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