失谐涡轮叶片模态特性分析

Modal Characterization Analysis of Mistuned Turbine Blades

针对涡轮增压器的涡轮叶片由于失谐产生的振动问题,建立涡轮叶片子结构模型并进行模态分析,绘制Campbell图,并对不同标准差失谐叶片进行固有频率和振型测量。结果表明,当叶片发生失谐时,周期性被破坏,一个或几个叶片振动异常,表现出振动局部化现象。因此,在设计时应避免应力集中导致涡轮叶片损坏,防止涡轮增压器发生故障。叶片随机失谐及叶盘结构共振特性之间的关系是研究叶片振动特性的关键,而研究这一环节可以保证运行稳定以及提升性能,对叶片失谐研究具有重要意义。

In order to solve the vibration problem caused by the detuning of the turbine blades of the turbocharger,the substructure model of the turbine blades is established,the modal analysis is carried out,the Campbell diagram is drawn,and the natural frequencies and mode shapes of the mistuned blades with different standard deviations are measured.The results show that when the blade is mistuned,it is periodically destroyed,and one or several blades vibrate abnormally,showing the phenomenon of vibration localization.Therefore,it is necessary to avoid damage to the turbine blades caused by stress concentrations and prevent the failure of the turbocharger during the design.The relationship between the random mistuning of blades and the resonance characteristics of blisk structure is the key to study the vibration characteristics of blades,and this link can ensure stable operation and improve performance,it is of great significance for the study of blade mistuning.