A Combined High and Low Cycle Fatigue Life Prediction Model for Wind Turbine Blades

A novel method is proposed for a combined high and low cycle fatigue (CCF) life prediction model based on Miner's rule, incorporating load interactions and coupled damage effects to evaluate the fatigue life of wind turbine blades under CCF loading. The method refines the CCF damage curve by modeling the complex damage evolution process under L-H loading and establishes a life prediction model linking low cycle fatigue (LCF) and high cycle fatigue (HCF) damage curves for more accurate predictions. Compared to Miner's rule, the M-H model, and the T-K model, the proposed approach demonstrates superior prediction accuracy, with results predominantly falling within a life factor of +/- 1.5. To verify the model's practical applicability, finite element analysis (FEA) was performed on critical blade sections, reducing the prediction error to 4.3%. This method introduces a novel approach for evaluating the fatigue life of wind turbine blades with improved accuracy over existing methods.