A Physics-Driven Digital Workflow for Damage Tolerance Assessment of Turbine Discs

This study proposes a physics-informed digital workflow for defect-tolerant life assessment of turbine discs, enabling efficient and scalable evaluation of crack growth behaviour across multiple defect scenarios. Turbine discs are fracture-critical aero-engine components whose structural integrity is strongly influenced by defect-driven fatigue crack growth. The proposed workflow integrates global finite element analysis, hotspot identification, local submodel extraction, and fracture-based life prediction within a unified computational chain linking structural response, defect morphology, and crack-driving mechanisms. Initial defects are idealized as equivalent cracks, and residual life is predicted by coupling FEM-derived local stress fields with a unified small-to-long crack growth model, enabling physically consistent evaluation across different defect sizes and locations. A representative turbine disc case is employed to demonstrate the workflow. The results show clear dependence of stress intensity factor and residual life on defect location, with surface defects generally more critical than subsurface or internal defects. Among the investigated regions, the dovetail root exhibits the shortest predicted residual life due to the combined effects of stress concentration, temperature, and local geometric constraint. Compared with repeated full-scale crack propagation simulations requiring crack-front remeshing, the proposed workflow improves computational efficiency by employing physically interpretable local submodels while retaining explicit representation of defect morphology and crack growth physics. The framework supports rapid screening of defect sensitivity and provides a computational basis for future inspection-informed updating and lifecycle structural integrity assessment.