涡轴-涡扇变循环发动机方案及性能匹配设计研究

Design and study on scheme and performance matching ofturboshaft-turbofan variable cycle engine

针对旋转机翼式垂直起降高速巡航飞行器,提出了一种新概念结构形式的涡轴-涡扇变循环(TSFVCE)发动机,能够分别在涡轴和涡扇两种模态工作。首先对涡轴-涡扇变循环发动机的结构及工作模式进行了介绍,并建立基于变比热的部件级性能仿真模型;然后通过循环分析,确定发动机第二涵道比为3,Flade外涵风扇压比为1.98,第一涵道比为0.11,完成发动机设计点性能方案设计;最后分析了核心机驱动风扇(CDFS)可调机构对发动机性能影响机理,得出CDFS放气阀对发动机涡扇模态下的推力与涡轴模态下的功率影响较大,对涡扇模态的推力影响最大为61.5%,对涡轴模态的功率影响最大为33.3%,可利用此特性实现发动机在涡扇和涡轴模态下推力和功率输出的匹配。

A new concept of turboshaft-turbofan variable cycle engine(TSFVCE)is proposed for vertical takeoff and landing and high-speed cruise aircraft with a rotor wing,which can work in both turboshaft and turbo⁃fan modes.Firstly,the structure and working mode of the TSFVCE are introduced,and the component perfor⁃mance simulation model based on varying specific heat is established.Then,the schematic design of the engine performance is completed through the cycle analysis,which determined that the second bypass ratio is 3,the fan pressure ratio of the outer bypass is 1.98,and the first bypass ratio is 0.11.Finally,the influence of core drived fan system(CDFS)adjustable mechanism on engine performance is analyzed,and it is concluded that CDFS bleeder valve has a great influence on the thrust of engine in turbofan mode and the power in turboshaft mode.The maximum impact on the thrust of the turbofan mode is 61.5%,and the maximum impact on the power of the turbo⁃shaft mode is 33.3%,which can be used to match the thrust and power output of the engine in the turbofan and turboshaft mode.