PSI - Issue 57

Laurent Dastugue et al. / Procedia Structural Integrity 57 (2024) 355–364 Michael Klein et. al./ Structural Integrity Procedia 00 (2019) 000 – 000

359

5

the unchanged process. There are three major improvements realized by integration. The process improvements itself, higher accuracy, and additional data efficiency. Figure 6 shows the integrated process.

Fig. 6. New integrated process.

3.1. Process improvements The integration of fatigue analysis with associated data organization solves the main problems in a natural way. The node stresses, for example, are available internally and only need to be processed further without intermediate storage. All analysis steps and the organization of the processes are within a maintained software. The software uses the same internal data formats and the high-performance infrastructure of the FE solver. The additional functionalities for the fatigue life analysis and for the process organization, see Figure 7, were implemented within the existing software. The stress results in the database are accessed directly. Then the fatigue stresses according to stress criteria in cutting plane are computed. After this the stress spectrum (σ m ≠ 0) is calculated by cycle counting Rainflow algorithm. The amplitude transformation is done with considering the mean stress influence by Haigh diagram to get the stress spectrum (σ m = 0). The Palmgren-Miner rule is used with the local SN curves to calculate the damage result.

Fig. 7. The fatigue steps of the new integrated process.