端面规则凹坑造型机械密封综合性能的数值分析

Numerical analysis of integrated performance of mechanical seals with regular micro-surface structure

考虑密封端面间液膜的空化现象和流体动、静压效应的相互影响,建立了端面规则凹坑造型机械密封的理论分析模型,利用多重网格法分析了在不同的密封系数下,球缺面凹坑的几何结构参数对端面间液膜开启力、摩擦转矩和液膜刚度的影响.结果表明,密封系数和微凹坑的深径比对密封性能的影响较大,密封系数越大,液膜开启力和刚度越大,存在最优的深径比使液膜开启力和刚度达到最大,且最优的深径比随着密封系数的增大而减小;面积密度对密封性能的影响不明显,存在最优的面积密度使液膜开启力和刚度达到最大,且最优的面积密度不受密封系数的影响.

A theoretical analysis model was developed to study mechanical seals with regular micro-surface structure considering cavitation within the fluid film between two faces and the interaction between hydrodynamic and hydrostatic components.Multi-grid method was used to study the effect of geometric parameters of dimples which in the form of spherical shape on the seal performance such as opening force,friction torque and fluid film stiffness for various seal parameters.The results show that the seal factor and the ratio of depth/diameter of dimple have significant effect on the seal performance.Opening force and fluid film stiffness increase as the seal factor increases,there have optimum values for the ratio of depth/diameter of dimple to maximize the opening force and fluid film stiffness respectively,and as the seal factor increases the optimum value of ratio of depth/diameter decreases.Area density of dimple has little effect on the seal performance,there have optimum values for the area density of dimple to maximize the opening force and fluid film stiffness respectively,and the seal parameter has not effect on the optimum value of area density.