Numerical Simulation Of Crack Propagation Due To Metal Fatigue

摘要

FEA model representing a metal object subjected to expected random vibration loadings during a predefined time period is received. Structural dynamic characteristics and responses of the FEA model are obtained. Cumulative damage ratios of all finite elements are computed using the obtained structural dynamic responses along with a S-N curve for the metal object, and predefined time period. Time and location of fatigue failure in the FEA model are determined by identifying which one of the finite elements fails first. The identified failed finite element's cumulative damage ratio reaches unity first. The FEA model is revised by removing the identified failed finite element. Then the revised FEA model is used for repeating the process of identifying another fatigue failure until the determined time of fatigue failure has passed the predefined time period. All identified failed finite elements represent simulated fatigue crack propagation.