Numerical simulation of rolling contact fatigue damage in pitch bearings using a damage-coupled constitutive model

Fatigue failure of pitch bearings critically affects wind turbine reliability. This study develops a Continuum Damage Mechanics (CDM) based elasto-plastic coupled framework to investigate rolling contact fatigue (RCF) in megawatt (MW)-level pitch bearings. Implemented via ABAQUS UMAT, the model integrates damage evolution from elastic and plastic deformations, quantifying damage accumulation and material property degradation. Results show distinct nonlinear characteristics in raceway fatigue and property degradation. Notably, elastic damage is found to dominate the RCF process in large-scale bearings. Parametric analyses indicate that higher surface hardness and compressive residual stress effectively inhibit damage and extend service life. By linking macroscopic structural response with microscopic damage evolution, this work provides a robust theoretical basis for lifespan prediction and reliability enhancement of critical wind turbine components under complex loading.