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In this paper, a mathematical model of a rotor-bearing system is presented. The model includes modal elastodynamics of a flexible rotor as well as the in-plane radial dynamics of the bearing with a flexible outer race. Elastodynamics of the flexible shaft utilises a solution based on Green's function to provide a computationally efficient approach. The flexible bearing outer race is modelled using Timoshenko beam theory. The system model also includes detailed lubricated contact mechanics of balls-to-races contacts with viscous friction. Therefore, the rotor-bearing analysis represents a detailed multi-physics tribodynamics and modal elastodynamic responses of the system which closely represents broad-band vibration response of such systems in practice, an approach not hitherto reported in the literature. It is also demonstrated that the outer race flexibility changes the location of the stability orbital centres, as well as the spread of limit cycle vibrations. Furthermore, it accentuates the occurrence of multiples of ball pass frequency. The importance of integrated system dynamics and lubricated contact mechanics is highlighted, showing that although the elastodynamic response of the rotor's flexible elements may not be clear in the acquired vibration signal, its effect on energy efficiency of the system can be quite important.

Constant Velocity Joint (CVJ) mechanisms enable torque transmission between two shafts at a fixed or variable angle. Cross groove CVJs are typically used in high performance automotive applications due to their versatility and light weight. Critical failure modes, such as pitting or abrasive wear, occur due to the harsh tribological conditions at ball reversals. In this research, an existing mathematical model is developed further for the case of cross groove CVJs including an accurate contact mechanics model. The developed model is validated against a published data set from literature. Surface topography of worn raceways are experimentally measured and the results from the developed model are corroborated with the measured surface parameters. This improved model shows the correlations between predicted contact force variation and wear scar depths during ball reversals, hitherto not reported in the literature.