Life and Reliability Software Tools for Turbopropulsion Systems

We propose to develop an innovative methodology for life and reliability prediction of hot-section components in advanced turbo propulsion systems where the effects of the high heat dwell environment must be predicted accurately. This includes the activation of synergistic time-dependent damage modessuch as creep, stress corrosion, and stress rupturein the presence of cycle-dependent fatigue crack initiation and growth. The proposed technology focuses on addressing the effects of these time-dependent damage modes in engine disks made from Nickel-based superalloys that could exhibit location-specific microstructures, microstructural variability, or evolution of microstructures after thermal exposures at elevated temperatures for extended time periods. The novel time-dependent fracture algorithm will be integrated with a commercial probabilistic life-prediction codecalled DARWIN(TM)thereby complementing and extending a suite of existing reliability analysis tools for turbine engines. This will provide a full-lifecycle reliability analysis tool for aircraft engines being considered in the VAATE program.