叶片展弦比对叶盘系统动频影响分析

以燃气轮机叶盘系统为研究对象,建立不同展弦比下的扭曲叶片和直叶片的叶盘系统结构模型,进行了叶盘系统的固有频率和振型分析,讨论了扭曲叶片和直叶片在不同展弦比下对叶盘系统动频影响的变化规律。结果表明:扭曲叶片和直叶片叶盘系统的展弦比对系统动频的影响变化规律是相同的;定宽度时,叶片展弦比对系统低阶频率的影响较小,高阶频率的影响较大,展弦比的增加使得叶盘系统的各阶频率均降低;定长度时,展弦比对叶片扭曲频率的影响比较敏感,会随着展弦比的增加而升高,其它各阶频率变化幅度较小。

Influence of Blade Aspect Ratio on Dynamic Frequency of Bladed Disk System

The gas turbine bladed disk system is taken as the research object, the structural models of twisted blade and straight blade blade system with different aspect ratios are established. The natural frequencies and vibration modes of the blade disk system are analyzed. The influence of twisted blade and straight blade on the dynamic frequencies of the blade disk system with different aspect ratios is discussed. The results show that the effect of the aspect ratio of twisted blade and straight blade on the dynamic frequency of the system is the same;when the width is fixed, the aspect ratio of blade has less influence on the low-order frequency of the system, but the influence of the high-order frequency is greater;the increase of aspect ratio makes all the order frequencies of the blade-disk system decrease;when the length is fixed, the aspect ratio of blade has less influence on the low-order frequencies of the system. It is more sensitive to the influence of blade twist frequency, and will increase with the increase of aspect ratio, and the other frequencies change slightly.