The proposed project will address the engine mission statistical modeling at the needed level of detail. Special attention will be given to the key mission aspects that influence the vibratory stresses in engine components and may produce their HCF failure. The proposed research will provide the following key capabilities: (i) a complete handbook on the statistical description of engine missions based on the available information from the Navy databases and (ii) an integrated software with tool boxes to compute the engine mission characteristics, to simulate random missions and to determine "representative" missions for life assessment analyses. The user-friendly software that will be developed will enable the engine design and/or maintenance engineer to visualize mission profiles, statistics, simulated mission sequences, and "representative" deterministic missions calibrated based on probabilistic life analyses. The proposed "representative" deterministic missions will be established for five different severity levels (extreme, very high, high, moderate and average) which will correspond to five non-exceedance probability levels in the probabilistic HCF/LCF life distribution. To compute "representative" missions for a given engine component the user has to input the steady and resonant stresses at critical locations for different speeds and strain-life and damage curve parameters.
Benefits: The software product developed by this effort can be directly used by the commercial engine manufactures to improve their engine design and reduce maintenance costs. With minimum adaptation the software can be applied to life assessment of any system, machinery or component that is subjected to random variable loading including aerospace, power and automotive industries.
Keywords: mission, engine, flight profiles, life prediction, HCF, probabilistics, cumulative damage
