PSI - Issue 30

L.A. Prokopyev et al. / Procedia Structural Integrity 30 (2020) 120–127 Prokopyev L.A. et al. / Structural Integrity Procedia 00 (2020) 000–000

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Fig. 4. Resulting temperature fields on the plate surface for scheme No.2.

In order to estimate the calculation accuracy of the "CINT" tool, the results of the finite element calculation were compared with the results obtained by Fett’s (1996) by the boundary collocation method for a plate with a centrally located crack, stretched by a uniform load. With a high-quality partitioning of the finite element mesh, the inaccuracy is no more than 0.15%. 3. Calculating the stress intensity factor, T-stresses and dimensions of the plastic zone by finite element method in plane strain and plane stress states For the plates shown in Fig.1 and Fig.2, a finite element model was built in the parametric design language "ANSYS APDL" and the stress intensity factor and T-stresses were calculated using the "CINT" tool. The results of calculating the stress intensity factor and T-stresses by the method of boundary collocations and finite element method are shown in Table 1.

Table 1. Comparing the results of calculation by finite element method and method of boundary collocations. Methods for determining the parameters of fracture mechanics Boundary collocation method by Fett (1996) .0 finite element method 3736.2 692.9 FEM inaccuracy relative to the boundary collocation method,% 0.03 0.14

By substituting the value of material yield point (1) into the equations of linear elastic fracture mechanics (2), the theoretical conditions for the appearance of a crack tip plastic zone are determined (3), that depends on loading parameters, such as the material yield point, Poisson’s ratio, stress intensity factor, and T-stress. Poisson’s ratio taken equal to 0.3.