对双外涵变循环发动机的模态转换过程进行了研究,设计了变循环发动机模态转换方案,确立了模态转换时的多部件调节规律,采用稳态模型对模态转换进行了数值模拟.结果表明,所设计的模态转换方案可行,能够使变循环发动机的涵道比发生明显改变,并有效提高了发动机在部分推力时的空气流量,与设计参数相同的常规涡扇发动机相比,其安装耗油率明显降低. The modal transformation process of double outer cogged cycle engine was studied, the modal transformation scheme of variable cycle engine was designed, the regulation rule of multi-component during modal transition was established, and the steady state model was used to simulate the modal transformation The results show that the designed modal transformation scheme is feasible, which can change the bypass ratio of the variable cycle engine significantly and increase the air flow of the engine under partial thrust effectively. Compared with the conventional turbofan engine with the same design parameters , Its installation of fuel consumption decreased significantly.