基于模态共振分析的某故障涡轮叶片改型设计

Retrofit Design of Turbine Blade Based on Modality and Resonance Analysis

某型发动机涡轮静子叶片在运作过程中经常出现断裂现象,为了保证飞机的安全运营,需要对故障叶片进行分析及改型处理。运用ANSYS进行模型建立及计算,对故障涡轮叶片进行模态分析。再对故障叶片进行延展改型并通过ANSYS进行验证,通过计算得到结论,改型后的叶片成功避开了原叶片发生故障时的事故频率,改型前后叶片1弯模态应力分布几乎一致,应力最大点和次大应力点均分别位于叶片前缘靠近顶部区域和叶片吸力面靠近顶部区域,且应力大小相差不大。由于避开了事故频率,到目前为止,使用过程中未再有断裂现象发生,从而验证了改型方案的可行性。

The blade fracture happened in a typical engine turbine stator. It is supposed to analyze and retrofit design the fractured blade to maintain safe operation. Using ANSYS, the blade model was established, and the modality was analyzed as well. Then retrofit design of the fractured blade was processed. The simulation result with ANSYS shows that redesigned blade avoids the accident frequency and that the distribution of 1st step stress is almost the same with that of fractured blade. The maximum stress and 2nd maximum stress appear respectively in the tip of the leading edge and in the tip of the suction side. The magnitude of these stresses is almost the same. What’s more, up to now, there is no more fracture phenomenon because of the absence of accident frequency, which indicates that the retrofit design is feasible.