叶片丢失激励下整机力学行为及其动力特性

Mechanical Behaviors and Dynamic Characteristics of Turbofan Engine due to Fan Blade Off

针对叶片丢失激励下航空发动机整机动力响应问题,分析了机匣、转子-支承系统以及安装节在内的整机结构系统的物理过程和力学行为。基于大涵道比涡扇发动机结构和力学特征,建立了转子系统动力学分析模型,并对其进行了数值仿真分析。结果表明:叶片丢失导致转子系统变为具有非对称时变参数特性的转子系统,其减速停车过程会对转子系统产生附加激振力,使转子系统的振动响应特征产生变化。为恶劣载荷激励下转子-支承结构安全性设计和结构动力学一体化设计提供理论基础。

Aiming at the dynamic response of the aeroengine due to blade off,the physical process and the mechanical behavior of the whole system,including casing,rotor-bearing system and the mount were analyzed.Based on the structural and the mechanical characteristics of the high bypass ratio turbofan engine,the mechanical model and mathematic model were established,and the numerical simulation was analyzed.The results indicate that the rotor system becomes asymmetric with time varying parameters,and the deceleration process would produce additional excitation force.The research provides a theoretical basis for the security analysis and structural dynamics integrated design of the rotor system due to blade off event.