Multi-Event Dynamics Modeling and Bidirectional Radial Response Analysis of Localized Groove Defects on the Outer Ring of Rolling Element Bearings

Localized bearing defects are often modeled as imposed displacements or instantaneous impacts, limiting continuous description of contact-state evolution. This study develops a multi-event ADAMS model for an axial-through outer-ring groove in an SKF 6208 bearing. The model retains rolling-element translational inertia, compliant Hertz/IMPACT contacts, and geometry-driven contact transitions. Relative angular position, local clearance, and contact deformation label the event states, while the continuous equations of motion determine the forces and trajectories. A directional sensitivity index uses dominant peaks around the defect fundamental and second harmonic. The model reproduces load release, short-term separation, trailing-edge impact, and contact recovery. At 1800 r/min, reconstructed experimental pulse-interval errors for 0.5, 1.0, and 1.5 mm grooves are 3.13%, 1.84%, and 0.86%, respectively. Speed governs passing frequency, whereas defect width and radial load mainly affect the simulated spectral-peak amplitude; circumferential position redistributes the response between the Y and Z directions. The expected event sequence and frequency/directional trends were confirmed. Absolute housing-vibration amplitudes and the magnitude of physical contact disruption were not calibrated: the component bodies and support path are rigid, the contact parameters were not identified from tests, and simulation displacement is compared with housing acceleration under different loads. The experimental comparison is therefore limited to pulse-period consistency and phenomenological parameter trends.