The service longevity of complex propulsion systems, such as the Space Shuttle Main Engine (SSME), can be at risk from several competing failure modes. Conventional life assessment practice focuses upon the most severely life-limited feature of a given component, even though there may be other, less severe, potential failure locations. Primary, secondary, tertiary failure modes, as well as their associated probabilities, must also be considered. Futhermore, these probabilities are functions of accumulated service time. Thus a component may not always succumb to the most severe, or even the most probable failure mode. Propulsion system longevity must be assessed by considering simultaneously the actions of, and interactions among, life-limiting influences. These include, but are not limited to, high frequency fatigue (HFF), low cycle fatigue (LCF), and subsequent crack propagation, thermal and acoustic loadings, and the influence of less-than-ideal nondestructive evaluation (NDE). An outline is provided for a probabilistic model for service life analysis, and the progress towards its implementation is reported.
Probabilistic model for fracture mechanics service life analysis
1988-09-01
Conference paper
No indication
English
Probabilistic/Fracture-Mechanics Model For Service Life
NTRS | 1991
|Probabilistic Fatigue Life Prediction for Ship Structures Using Fracture Mechanics
British Library Conference Proceedings | 2000
|Fracture Mechanics and Service Life Prediction Research
NTIS | 2001
|Probabilistic finite elements for fracture mechanics
AIAA | 1988
|