失谐叶栅的受迫振动响应特性分析

采用基于计算流体力学(CFD)方法的降阶气动力模型并耦合结构运动方程,实现了存在外激励载荷时失谐叶栅受迫振动响应的快速分析。针对典型的跨声速叶栅,通过求解其位移响应幅值较系统地研究了失谐方式、失谐强度和叶片质量比对失谐叶栅受迫振动响应幅值的影响。研究表明文中刚度失谐形式可以改善叶栅振动的稳定性,同时导致系统受迫振动响应局部化程度的增加,并且受迫响应的最大振幅放大因子随失谐强度增加或者质量比降低存在先增大后减小的一个峰值,不同失谐形式则对这个峰值的大小有着明显的影响。由于该方法可高效地分析失谐叶栅受迫振动各参数对模态局部化的影响,在工程上有一定的应用价值。

Characteristics analysis of forced vibration response of mistuned cascades

This paper employs a reduced order aerodynamic model based on Computational Fluid Dynamics (CFD),coupled with the structural dynamic equation,to analyze the forced vibration response of the mistuned cascade.The displacement amplitude of the typical transonic cascade in the tuned and mistuned cases are calculated by the proposed method,and the effect of mistuning patterns,mistuning strengths and mass ratios on the forced vibration response amplitude of the mistuned cascade are investigated quantitatively.The results show that the stiffness mistuning patterns in this paper can improve the stability of the cascade,but can also result in the increase of the modal localized level.The maximum vibration amplitude magnification factor has a peak value as the mistuning strength increases or the mass ratio decreases,and the peak value is significantly affected by mistuning patterns.Due to its efficiency in the analysis of the modal localization of the mistuned cascade with forced vibration,the proposed method is beneficial for engineering applications.