高速气流阻塞效应对倾斜微孔端面密封动压特性的影响  

The Effect of High Speed Airflow Lubrication on Hydrodynamic Properties of Inclined-Dimples Face Seals

作　　者：谢静[1] 白少先[1] 

机构地区：[1]浙江工业大学机械工程学院,浙江杭州310032

出　　处：《摩擦学学报》2017年第6期806-813,共8页Tribology

基　　金：国家自然科学基金项目(51275473);浙江省自然科学基金杰出青年基金项目(LR14E050001)资助~~

摘　　要：以倾斜椭圆微孔端面为研究对象,考虑出口阻塞效应和入口压力损失,对高速气流润滑密封动压特性展开理论研究.采用数值方法重点分析不同密封压力、转速等操作参数和端面宽度等几何参数以及方向因子、倾斜角、孔深及面积比等微孔几何参数下,阻塞效应对开启力和泄漏量等密封特性参数的影响规律.结果表明:入口压力损失使入口处压力降低,出口阻塞效应使出口处压力抬升,导致端面开启力和泄漏量降低.随着转速和密封压力的增加,阻塞效应增强,与强制压力边界下的值相比,当密封压力为10 MPa,转速为50 000 r/min时,开启力降低可达5%以上,泄漏量可降低67%以上.当孔深取2~4μm,微孔倾斜角取20°~40°时较易获得优异的动压开启性能.The hydrodynamic properties of high speed airflow lubrication of inclined-ellipse-dimples face seals were theoretically studied with consideration of choked flow effect and entrance pressure loss. Influence of the choked flow effect on the sealing parameters, opening force and leakage rate, was numerically analyzed under different operating conditions of seal pressure and rotational speed. Meanwhile, influence of geometric parameters（e.g. seal face width） and texturing parameters（e.g. slender ratio, inclination angle, dimple depth and dimple area rate） were also discussed. The results show that the entrance pressure loss led to drop of the inlet pressure while the choked flow effect increased the exit pressure, which resulted in the decrease of the opening force and the leakage rate. The choked flow effect increased with increasing rotational speed and seal pressure. Compared to the values under the coercive boundary, the opening force decreased more than 5% in the cases of the seal pressure 10 MPa and the rotational speed 50 000 r/min, and the leakage rate decreased more than 62%. In order to obtain better hydrodynamic opening force, 2~4 μm dimple depth and20~40° dimple inclination angle were recommended.

关 键 词：倾斜椭圆微孔 端面气膜密封 阻塞效应 动压效应 

分 类 号：TB42[一般工业技术]