汽轮机转子T型叶根-轮槽系统力学分析

摘要

The integral model of T root-rim system of the steam turbine blade was established. Moreover, the static and dynamic stress in resonance state of the T-root and root groove were calculated. The high-cycle fatigue safety factor of the T-root groove was analyzed by Goodman method. The results show that, the fillets and the external small angle of the blade root, and the fillets on the end wall and both outsides of the T-root groove are critical areas, which is consistent with the areas of the T-root groove in the failed blade. The proposed method can provide designers with the theoretical basis for designing high-cycle fatigue safety performance of the T-root and root groove, and also provide the operators and inspectors with the critical component of the monitoring and inspection of the T-root and root groove.%本文采用有限元分析法建立了汽轮机转子T型叶根-轮缘系统的整体模型,计算出汽轮机转子T型叶根及叶根槽的静应力及共振状态下动应力,并基于Goodman曲线方法对汽轮机转子叶根及叶根槽进行高周疲劳安全系数分析.分析计算结果表明,叶根上倒角及外包小角、叶根槽端壁上倒角处以及两侧外包倒角处是较易发生疲劳裂纹的部位,与实际中已发生疲劳失效的叶根槽位置相符.该结果可为T型叶根及叶根槽高周疲劳安全性能设计及检查监测提供参考.