TITLE:
Creep-Fatigue Interaction Life Consumption of Industrial Gas Turbine Blades
AUTHORS:
Ebigenibo Genuine Saturday, Thank-God Isaiah
KEYWORDS:
Creep Damage, Fatigue Damage, Creep-Fatigue Interaction, Creep-Fatigue In-teraction Factor
JOURNAL NAME:
Modern Mechanical Engineering,
Vol.8 No.4,
October
19,
2018
ABSTRACT: This paper presents the creep-fatigue interaction
life consumption of industrial gas turbine blades using the LM2500+ engine
operated at Pulrose Power station, Isle of Mann as a case study. The linear
damage summation approach where creep damage and fatigue damage are combined
was used for the creep-fatigue interaction life consumption of the target
blades. The creep damage was modelled with the Larson-Miller parameter method
while fatigue damage was assessed with the modified universal slopes method and
the damage due to creep-fatigue interaction was obtained from the respective
life fractions. Because of the difficulty in predicting the life of engine
components accurately, relative life consumption analysis was carried out in
the work using the concept of creep-fatigue interaction factor which is the
ratio of the creep-fatigue interaction life obtained from any condition of
engine operation to a reference creep-fatigue interaction life. The developed
creep-fatigue interaction life consumption analysis procedure was applied to 8
most of real engine operation. It was observed that the contribution of creep
to creep-fatigue interaction life consumption is greater than that of fatigue
at all ambient temperatures. The fatigue contribution is greater at lower
ambient temperatures as against higher ambient temperatures. For the case
study, the overall equivalent creep-fatigue factor obtained was 1.5 which
indicates safe engine operation compared to the reference condition. The developed
life analysis algorithm could be applied to other engines and could serve as
useful tool in engine life monitoring by engine operators.