Hydrodynamic Lubrication in Wavy Contacting Face Seals—A Two Dimensional Model

Abstract

The role of circumferential surface waviness in contacting mechanical face seals is examined. First, a two dimensional model is developed. The model considers waviness amplitude, surface roughness, asperity contact, hydrodynamic and hydrostatic pressures, and fluid cavitation. Given waviness, roughness, number of waves, geometry, and sealed fluid, the model predicts the fraction of load supported by fluid pressure, the relative wear rate, friction coefficient, and leakage rate. A numerical method for solving this problem is presented. Using this model, the effects of waviness amplitude, roughness, number of waves, face width, and sealed pressure on seal performance are examined. Based on these results, certain conclusions are reached concerning the role of waviness in commercial face seals. Finally, using the model, it is shown how waviness can be applied to advantage to reduce seal friction and wear rates.