Modeling Mixed Lubrication of Bearings

Seawater lubricated propulsor (i.e., stern tube) bearings are one of the most important bearings aboard a ship. The performance and life of these bearings directly affects the vessel's operational capabilities, life cycle costs, and overall availability. In a single shaft vessel such as a Columbia class SSBN, any failure of this bearing is extremely problematic. In certain applications such as submersibles, these bearings are thermoplastic or elastomer liner partial arc bearings. Adequate design and analysis tools for these bearings are not currently available. Thus, it is difficult to optimize bearing designs for new and in-service applications. Development must rely on approximate design methods and costly testing.To meet these needs, Xdot is developing and experimentally validating new bearing analysis software which is capable of accurately predicting performance over the full operating envelope, including the boundary, mixed and hydrodynamic regimes. The Phase II goal is to advance the analysis tool software to Technology Readiness Level 7+. The effort to achieve this goal includes software development, enhancing the bearing test rig for larger bearings as well as higher ambient pressures, and generation of validation test data.