Thermoelastohydrodynamic Gas Lubrication of Spiral-Groove Face Seals: Modeling and Analysis of Vapor Condensation

ABSTRACT

Vapor condensation in gas lubrication of high-pressure spiral-groove face seals is analyzed in this article. A mathematical model of vapor condensation elastohydrodynamic lubrication (EHL) is developed taking into account gas humidity and thermoelastic deformation of seal rings. Vapor condensation is numerically predicted at high speed and pressure. It is found that vapor condensation usually occurs in the sealing dam region, where the lubrication state changes from gas lubrication to gas–liquid lubrication. The vapor condensation rate increases with an increase in humidity and seal pressure. Under high-pressure conditions, seal clearance has a significant influence on the vapor condensing rate but the rotational speed does not.

KEYWORDS:

• EHL
• vapor condensation
• gas face seal
• thermal effect

Funding

This research is financially supported by the National Nature Science Foundation of China (No. 51275473), the Zhejiang Province Natural Science Fund for Distinguished Young Scholars of China (No. LR14E050001), and the Tribology Science Fund of State Key Laboratory of Tribology of China (No. SKLTKF14B13).