小失谐叶轮的固有振动分析

失谐的带有 N个叶片的叶轮, 由于失去了 N阶回转对称性, 用于谐调叶轮的群论方法不再适用, 给其固有振动分析造成了困难。本文根据摄动理论, 以谐调叶轮的主模态作为 Ritz基, 提出了一种适用于小失谐叶轮固有振动分析的模态综合技术。算例表明, 文中方法是切实可行的。 

NATURAL VIBRATION ANALYSIS OF TURBOMACHINERY DISK WITH SMALL MISTUNED BLADES

A numerical approach is developed for natural vibration analysis of turbomachinery disk with small mistuning blades by using modal synthesis technique.Due to lack of rotational periodicity,the group theory method for the tuned bladed disk assemblies is not applicable to the mistuned ones.According to the matrix peturbation theory,the modes used for synthesis in this paper are taken from a tuned bladed disk corresponding to the small mistuning one.This new technique keeps the advantages of the group theory method and makes the final eigenvalue problem of small size.A computer program has been written to analyse the natural vibration characteristics of turbomachinery disk with small mistuning blades.The computational results prove that the method is very efficient.