机动飞行条件下双转子系统动力学建模与响应分析

考虑航空发动机双转子中介轴承的耦合作用及陀螺力矩的影响,利用Lagrange方程建立了机动飞行条件下双转子-滚动轴承支承耦合系统动力学模型，对耦合双转子系统的动力学特性进行了理论与实验研究.结果表明:随着内外转子转速比增大，高压转子振动幅值减小，分岔点处转速增大，最大增幅近67.49%.机动飞行使转子的振动响应幅值增大，出现较多分频.在跃升和横滚飞行姿态下，高压转子响应主要表现为:随着跃升速度增加，高压转子振动幅值明显增加，最大增幅近409.24%，分岔点对应的速度增大；在横滚速度增大时，转子振动特性主要表现为从复杂的运动形态变换到单周期运动形态,转子的振动幅值明显增加.利用基础运动双转子模型实验台对跃升和横滚两种飞行姿态下耦合双转子系统的部分动力学特性进行了实验研究,实验结果与数值模拟结果有较好的一致性，证明了计算结果的正确性. 

Modeling and response analysis of dual-rotor system under maneuvering flight

Considering the coupling effect of intershaft bearing and the influence of gyroscopic moments,a dynamic model of a dual-rotor-ball bearing coupling system under maneuvering flight was established by using Lagrange's equation,whilst theoretical and experimental study were both carried out.It is shown that with the increase of speed ratio of inner and outer rotors,the vibration amplitude decreases and the speed of bifurcation point grows with a maximum rate about 67.49 ％.The rotor's vibration amplitude increases and more frequencies appear under maneuvering flight.With the increase of leaping flight speed,the outer rotor's vibration amplitude increases obviously with a maximum rate about 409.24％,the speed of bifurcation point grows at the same time.During rolling flight,the rotor's period doubling bifurcation point disappears in contrast to the system without maneuvering flight,but the vibration amplitude increases obviously.By using a model experiment rig of a dual-rotor system under maneuvering flight,parts of dynamic characteristics of outer rotor have been studied,and the experimental and numerical simulation results are in good agreement.