椭圆型表面织构对机械端面密封动压性能的影响

Effect of Elliptical Dimples on the Hydrodynamic Properties of Mechanical Face Seal

根据表面织构可以有效改善相对运动表面的摩擦学性能,建立均匀分布的椭圆型微凹坑机械端面密封的理论模型,采用有限差分法对流体动压润滑方程进行求解,获得密封端面间气膜的无量纲压力分布,研究椭圆倾斜角α和形状系数t对压力分布的影响,并考察整个密封端面的平均无量纲压力Pav。结果表明:当t≥1时,密封端面平均无量纲压力Pav随着倾斜角α的增大呈现减小趋势,反之t<1时呈增大趋势;不同倾斜角α下,Pav随着形状系数t的增大先增大后减小;通过选择合理的椭圆倾斜角和形状系数,相比于圆凹坑端面可提高约7%的平均无量纲压力。

With surface texturing being efficient in modifying the tribological performances of relatively moving surface, a theoretical model of mechanical face seal within equally distributed elliptical dimples was developed.The finite difference method was employed to calculate the hydrodynamic lubrication equation, and the dimensionless pressure distribution of the gas film between the face seal was obtained. The effect of influence parameters of inclination angle α and shape factor t on the pressure distribution was evaluated and the average dimensionless pressure Pavof the whole face seal was also investigated. The results show that,the average pressure Pav shows a downward trend with the increasing of α when t ≥ 1, otherwise, it shows an upward trend; The average dimensionless pressure Pavfirstly increases and then decreases with the increasing t when the inclination angle has different values. Further analysis demonstrates that the average dimensionless pressure can be improved by about7% through the reasonable choice of inclination angle and shape factor.