Probabilistic Rotor Life Assessment Using Reduced Order Models

Abstract

Probabilistic failure assessments for integrally bladed disks are system reliability problems where a failure in at least one blade constitutes a rotor system failure. Turbine engine fan and compressor blade life is dominated by High Cycle Fatigue (HCF) initiated either by pure HCF or Foreign Object Damage (FOD). To date performing an HCF life assessment for the entire rotor system has been too costly in analysis time to be practical. Although the substantial run-time has previously precluded a full-rotor probabilistic analysis, reduced order models make this process tractable as demonstrated in this work. The system model includes frequency prediction, modal stress variation, mistuning amplification, FOD effect, and random material capability. The model has many random variables which are most easily handled through simple random sampling.

A state-of-the-art review on uncertainty analysis of rotor systems

“…It will certainly make meaningful progress if the uncertainty analysis is applied in practical scenarios with efforts to promote the most advanced theory. For these cases, the ROMs can alleviate the computation burden to some extent [299,300]. It also remains unclear which UQ methods will benefit most from the joint use of the reduced-order modeling.…”