拉杆对高速柔性转子动力特性的影响

摘要

针对采用两种不同拉杆方案的低压转子，分别建立有限元分析模型，在4种组合支承刚度下，运用SAMCEF/ROTOR分析软件完成低压转子的动力特性（临界转速、振型及稳态不平衡响应）计算，通过对比分析得到拉杆对低压转子动力特性的影响。研究表明：长拉杆方案和短拉杆方案对低压转子的前三阶临界转速和前两阶振型没有实质性的影响，但对第三阶振型和稳态不平衡响应有显著影响。研究结果为某小型涡扇发动机工程设计阶段的低压转子结构设计提供了参考。%Finite element models of a low-pressure rotor with two different draw-bars were set up respectively. The dynamic characteristics, including critical speeds, vibration modes and stable unbalance responses, of the rotor with four different supporting stiffness conditions were calculated by SAMCEF/ROTOR software. The influence of different draw-bars on the dynamic characteristics of the rotor was analyzed according to the calculation results. The results show that the length of the draw-bar has no influence on the first three-order critical speeds and the first two-order vibration modes of the low-pressure rotor, but has remarkable influence on the third vibration mode and stable unbalance responses. This work may provide a reference for structure design of the low-pressure rotor.