双转子系统振动特性分析

Analysis of vibration Characteristics of Dual-rotor System

为了深入剖析先进高推重比涡扇发动机双转子耦合系统的动力学特性,建立典型的双转子系统耦合力学模型,通过拉格朗日方程得到转子系统振动微分方程解析表达式.根据解析解,得到影响双转子系统振动特性的关键特征参数,并详细讨论转速比和转动方向对高、低压转子的共振频率,不平衡响应和涡动轨迹的影响.结果表明:通过高、低压转子转速比的合理选取,可以有效地抑制转子系统的振动,对航空发动机转子系统结构特征参数的选取有着重要的指导意义.

In order to analyze the dynamic characteristics of a dual-rotor coupling system of advanced turbofan engines with high thrust-weight ratio,a typical coupled mechanical model of a dual rotor system is built,and the analytic expression of the vibration differential equation of the rotor system is obtained by the Lagrange equation.According to the analytical solution,the key characteristic parameters that affect the vibration characteristics of the dual rotor system are obtained.The influence of the rotational speed ratio and the rotation direction on the vortex frequency,the unbalanced response and the vortex path of high and low-pressure rotors is also discussed in detail.The result shows that the vibration of the rotor system can be effectively restrained through reasonable selection of rotor speed ratio of high and low-pressure rotors,which has an important guiding significance for the selection of structural characteristic parameters of the aero-engine rotor system.