唇形密封轴表面方向性微孔的润滑特性

摘要

In order to study the effects of shaft surface inclined micropores on lubrication performance of lip seal, a mathematical model of lip seal under steady state was developed based on mass conservation with Jakobsson-Floberg-Olsson (JFO) cavitation boundary condition. The lubrication governing equation was solved by the finite element method, and the non-dimensional reverse pumping rate and friction force were obtained, then a comparative study of lip seal lubrication performance for different shaft surface inclined micropores shapes (ellipse, rectangle, diamond, isosceles triangle) was conducted. Micropores symmetrical with the shaft tangential direction produced zero reverse pumping rate, while others with 45° inclination to the axial direction produced maximum reverse pumping rate. Friction force was minimum when the micropore oil wedge dimension along the tangential direction was minimum. Reverse pumping rate and friction force decreased with micropore depth. Micropores with higher shape factor could produce higher reverse pumping rate and lower friction force. Rectangle micropore produced the maximum reverse pumping rate and minimum friction force among four kinds of micropores under the same conditions.%为研究方向性微孔对唇形密封润滑特性的影响，建立了遵循质量守恒的JFO空化边界条件的唇形密封润滑理论模型，采用有限单元法求解雷诺控制方程，获得了泵汲率、摩擦力等性能参数，对比分析了椭圆形、矩形、菱形、等腰三角形4种不同形状方向性微孔织构唇形密封的润滑特性。结果表明：微孔结构对称于轴切向时泵汲率为零，而与轴线呈45°倾斜时具有最大泵汲率；微孔结构沿轴切向形成的油楔尺寸最小时，具有最小摩擦力；增加微孔深度将使泵汲率下降，但能减小摩擦力；增大形状因子既可以提高泵汲率，又能减小摩擦力；相同条件下，矩形微孔具有最大泵汲率和最小摩擦力。