The Numerical Simulation Of Fatigue Crack Growth Based On The Element-free Galerkin Method

Practical projects, fatigue failure is quite common, in the destruction of the structure of failure prediction, simulation of the fatigue crack growth has become very important. No grid method is the rise of a new numerical method in recent years, With the traditional finite element method compared, No grid method only need node information and computational domain of the geometric borders, overcome the finite element method dependent on the grid.In dealing with fatigue crack growth, the no grid method only needs through free crack or crack line to simulate the extension of lines, which greatly simplifies the simulation process of fatigue crack growth, the crack growth with non-grid method has its unique advantage. The Element-free Galerkin Method based on Mobile Least Squares Approximation Theory, with its high accuracy, good stability and convergence characteristics of fast become the most promising one。Practical projects, fatigue crack often in the form of compound, the fatigue crack growth simulation of compound needs to choose a convenient and accurate calculation of the fracture criteria to calculate the crack growth direction, Maximum circumferential stress criteria is in a wide range of applications because of the advantages of the calculation of convenience, some scholars have put forth some revised criteria according to the criteria inadequate, but also increase the amount of calculation, in this paper on the basis of its revised criteria, present its revised criteria simplified model.Fatigue crack growth, the stress intensity factor solution is the key to solve the problem. Meshless-direct displacement method directly through no grid method of extrapolation displacement to obtain the crack tip stress intensity factor, which is calculated on the stress intensity factor provides a new way, this paper discussed the impact on the calculation accuracy for the choice of extrapolation nodes and crack encryption.Through continuous incremental linear simulation crack growth, it obtain crack growth directionstress and intensity factor amplitude according to simplify the calculation model, it obtain fatigue crack growth life according to generalized rules Paris, in this paper,it give solving process of the fatigue crack growth of The Element-free Galerkin Method and preparate the of the core program of The Element-free Galerkin Method with Fortran.The correctness of procedures is Proved through the focus on the role of the cantilever, the expansion process of EFGM simulation is given through centre cracks of rectangular plates.