NAVAIR's mission is to provide full life-cycle support of naval aviation aircraft, weapons and systems operated by Sailors and Marines. In partnership with Southwest Research Institute, this award was granted for work on “Life and Reliability Software Tools for Turbopropulsion Systems”.

The purpose of this award was 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 modes such as creep, stress corrosion, and stress rupture in the presence of cycle-dependent fatigue crack initiation and growth.

The technology developed 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 was integrated with a commercial probabilistic life-prediction code called DARWINTM thereby complementing and extending a suite of existing reliability analysis tools for turbine engines. This provided a full-lifecycle reliability analysis tool for aircraft engines being considered in the VAATE program.

White Paper: A Microstructure-Based Time-Dependent Crack Growth Model for Life and Reliability Prediction of Turbopropulsion Systems

International Journal of Fatigue Article: Mitigating Time-dependent Crack Growth in Ni-base Superalloy Components

Applications of Reliability Assessment