The behavior and life of a tilted flat thrust washer bearing is modeled by a comprehensive numerical code. The goal is to investigate the conditions that distress thrust washer bearings through numerical techniques. This work includes thermomechanical deformations (which have been neglected in previous studies). The thrust washer bearing supports non-axisymmetric loads within the planetary gear sets of automatic transmissions and consists of flat-faced washers placed between an idle helical gear and its contacting face. Various coupled numerical schemes model sliding friction, boundary lubrication, asperity contact, thermo-mechanical deformation, thermo-viscous effects, and full film lubrication. The model provides predictions of frictional torque, bearing temperature, hydrodynamic lift and other indicators of bearing performance. The experimental and numerical results show that the bearing is very susceptible to the mechanism of thermoelastic instability (TEI). Theoretical predictions indeed predict that the washer may operate in the range of TEI.
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