PSI - Issue 25

Corrado Groth et al. / Procedia Structural Integrity 25 (2020) 136–148 C. Groth et al. / Structural Integrity Procedia 00 (2019) 000–000

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Fig. 9: Elliptical cracks shape evolution: comparison with 2DOF model

(a) Evolution of peak SIF ratio

(b) Evolution of peak J integral ratio

Fig. 10

(b) Trend of J integral along the crack length

(a) Comparison of the shape evolution of the elliptical crack 10x15 after 7280 cycles

Fig. 11

4. Conclusions

In this paper a review of applications tackling numerical fracture machanics, obtained by exploiting FEA (An sys Mechanical) and mesh morphing (RBF Morph) state of-the-art tools, was given. Two di ff erent approaches were presented in order to study the flaw evolution by deforming the computational grid according to the Paris-Erdogan law using Radial Basis Functions (RBF). At first a 2 degree of freedom model was implemented, guiding the in-plane crack development by using two stress intensity factor (SIF) values, one on the in-depth point on the symmetry and one on the surface. This model was then improved by evaluating the SIF along the crack profile, guiding its evolution by projecting the displacements along the crack normals. These two approaches were at first demonstrated on a notched