Probabilistic fatigue design of gas turbine compressor blades under aleatory and epistemic uncertainty
2016 (English)Report (Other academic)
In this work, a new method for fatigue probability assessment is introduced. The method is applied to a bladed disk in a gas turbine for computation of the fatigue probability for a specific load case. Both epistemic and aleatory uncertainties are modeled. The aleatory uncertainty is of two types: Type 1 aleatory uncertainty is modeled by use of stochastic variables that influence the problem, including both design variables and stochastic parameters. Type 2 aleatory uncertainty is modeled by use of a probability that remains even if all stochastic variables are replaced by deterministic values. The fatigue behavior of a material exhibits type 2 aleatory uncertainty. The results show that the epistemic uncertainty in the modeling of the aero-forcing and the damping gives a large uncertainty in the computed failure probability. The new method is also used to study the influence on the probability of fatigue that comes from the stochastic variables.
Place, publisher, year, edition, pages
2016. , 20 p.
failure probability, fatigue assessment, high cycle fatigue, uncertainty, compressor blade
Research subject Solid Mechanics
IdentifiersURN: urn:nbn:se:kth:diva-182430OAI: oai:DiVA.org:kth-182430DiVA: diva2:904439
QC 201602192016-02-182016-02-182016-02-22Bibliographically approved