Study of rolling contact fatigue behavior of a wind turbine gear based on damage-coupled elastic-plastic model

Abstract Gear contact fatigue has a significant influence on the reliabilities of heavy-duty gear-driven machines such as wind turbines. In the present work, an elastic-plastic contact fatigue model in conjunction with damage is developed to study the fatigue performance of a megawatt wind turbine gear. In this model, damages caused by both elasticity and plasticity are considered based upon the continuous damage mechanics (CDM) in the frame of ABAQUS using a user material subroutine. Damage accumulation and the evolution of the material mechanical properties are recorded during the fatigue crack initiation life. The contributions of elastic damage and plastic damage are distinguished. The effect of applied load on the contact fatigue life is studied and the stress–life curve is fitted based upon the numerical data. Results show that under a wide range of load conditions, the contact fatigue of the gear is always dominated by the elastic damage.