Fault-to-Failure Progression Modeling of Propulsion System and Drive Train Bearings for Prognostic and Useful Performance Life Remaining Predictions

"Sentient Corporation, in partnership with The Timken Company and the Mechanical Engineering Tribology Laboratory (METL) at Purdue University, proposes the development of comprehensive and accurate fault initiation/progression models for rollingbearings. Models will be developed for all common bearing spalling modes based on: (1) existing data from bearing manufacturer qualification testing; (2) new data from seeded fault experiments conducted by METL and Timken; (3) available experience datafrom military sources; and (4) further development of existing analytical and computer models for elasto-hydrodynamic lubrication, accumulated plastic strain, and energy dipole damage theories. Statistical variability in the experimental data will becarefully analyzed to allow measures of confidence and bounds to be generated along with useful life remaining. Phase I will focus on the analysis of existing data sets from Timken, METL, and military/contractor sources, and the fusion of this data with current theoretical models for surface fatigue. Phase II will expand upon the models and fill the gaps inexisting datasets through a spall propagation testing program utilizing the facilities at Timken's research center, and through ground-based and in-flight aircraft component data collection. Additional material wear, fatigue, and temperature degradationexperiments will also be conducted at METL to support the theoretical basis for the models.