The crack Growth Analysis on a Real Structure Using the X-FEM and EFG Methods

Gordana Jovičić, PhD (Eng)

Miroslav Živković, PhD (Eng)

Katarina Maksimović, MSc (Eng)

Nenad Đorđević, MSc (Eng)

 

The finite element method is the most universal and the best known one among numerical methods. However, for solving problems with specific conditions, such as singularities in the case of fracture mechanics and the crack growth, the EFG (Element-Free Galerkin) and the X-FEM (Extended Finite Element Method) are the methods that have advantages in comparison to the standard FEM. In this paper, we have shown the numerical simulation of the crack growth in the steam turbine housing using standard FEM, X-FEM and EFG method. For calculation of the stress intensity factors (SIFs) we used the J-integral. In this paper equivalent domain integral (EDI) method for evaluation of the J-integral is presented. The J-EDI method for determining SIFs in the standard FE, the X-FE and the EFG framework is used. Using the developed software, the stress intensity factors of the steam turbine housing were calculated and compared with the corresponding results obtained with conventional FEM software.

Key words: fracture mechanics, crack, crack growth, finite element method, element free galerkin method (EFG),    X-FEM method, J-integral.