Effect of operating conditions on turbine rotor blade creep life

Based on Larson-Miller parameter, the effects of high pressure turbine relative rotational speed, flight altitude H and radial temperature distribution factor (RTDF) on turbine rotor blade creep life were analyzed quantitatively when these parameters deviated from design condition. The results show that when high pressure turbine relative rotational speed is reduced by 2% from its reference value, both the blade temperature and blade stress decrease by 6%. The creep factor increases substantially from 1 to around 186 in terms of blade root. With the increase of H, blade temperature increases and blade stress decreases. In terms of blade root, when H is deviated from its reference value, the creep factor is reduced under the combined action of temperature and stress. Far away from the blade root, the effect of temperature is more important and creep factor increases with the decrease of H. When RTDF reduces, the blade temperature decreases and creep factor increases.