PSI - Issue 38

8

Christophe Grosjean et al. / Procedia Structural Integrity 38 (2022) 94–108 C.Grosjean and al. / Structural Integrity Procedia 00 (2021) 000 – 000

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Fig. 7. (a) Hydraulic block during fatigue tests with the inlet on the left and the outlet closed on the right. (b) Location of crack initiation sites

8. Computing and testing correlations 8.1. Calculation Model

First of all, the thickness of the groove base has been measured locally to come up with an optimized CAD model. The Finite element analysis (FEA) made by ANSYS Workbench was performed from this optimized CAD model and with the same boundary conditions used on the experimental fatigue test bench (see Fig. 7). The model boundary conditions for the model consist in symmetry condition (half of the model was meshed) and fixed boundary condition on the hydraulic coupling (see Fig. 8). The hydraulic block is fixed by bolt joint on two parts like the one used in the test facilities (The fixed boundary condition is considered as no translation, no rotation). The bolt pre-stress is considered in the calculation as mentioned in §3. For the computation, a contact nonlinearity is considered between the two additional parts and the hydraulic block as seen in Fig. 9a. The loading is a pressure variation inside the hydraulic block only as seen on Fig. 9b (no pressure in the groove)

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Symmetry condition (in blue)

Fixed boundary condition

Fig. 8. (a) symmetry conditions (in blue). (b) fixed boundary condition (in blue)