服役工作条件对涡轮转子叶片蠕变寿命的影响

基于Larson-Miller蠕变寿命理论,定量地分析了高压涡轮相对转速、飞行高度H、径向温度分布系数(RTDF)偏离设计状态时对涡轮转子叶片蠕变寿命的影响.结果表明:以叶根位置来看,高压涡轮相对转速从参考状态减小2%,导致叶片温度减小6%,叶片应力减小6%,使蠕变寿命因子从1增大到186.H增大导致叶片温度增大、叶片应力减小.从叶根位置来看,在温度和应力的综合作用下,H偏离参考状态时,蠕变寿命因子减小;而远离叶根位置,温度对蠕变寿命因子的影响越来越大,蠕变寿命因子随着H的减小而增大.RTDF减小导致叶片温度减小,使蠕变寿命因子随之增大.

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.