As a propulsion system for vertical take-off and landing (VTOL) aircraft, the gas-driven fan propulsion system has received some attention in recent years due to its simple mechanical structure and good performance. During the operation of the propulsion system, the core turbofan exhaust is directed to the tip turbine to drive the ducted fan to obtain thrust, and the louvered vector exhaust device is used to achieve lift/thrust switching. However, due to the linkage characteristics of the guide vanes of the exhaust device, the exhaust area will gradually change with the deflection of the guide vanes. This may cause uncertain effects on the system. Besides, considering the development cost of the propulsion system, it is necessary to clarify whether the core turbofan needs to be redesigned based on the characteristics of the system. Further, the transitional performance (VTOL to flight) of the propulsion system also needs to be studied. To this end, this study established an overall model of the gas-driven fan propulsion system combined with the characteristics of the core turbofan to analyze these problems. The results indicate that the louvered vector exhaust device can well match the gas-driven fan propulsion system. And when the propulsion system is composed, the gas-driven fan will not significantly affect the operation characteristics of the core turbofan. Besides, the preliminary analysis shows that the gas-driven fan propulsion system can meet the power requirements of the transition state of the fixed-wing VTOL aircraft. And the characteristics of the propulsion system may make the take-off thrust-weight ratio requirement of the fixed-wing VTOL aircraft be as low as 1.1.

作为垂直起降（VTOL）飞机的推进系统，气体驱动风扇推进系统由于其机械结构简单、性能优良等特点，近年来受到了一定的关注。推进系统运行过程中，核心涡扇排气直接进入叶尖涡轮驱动涵道风扇获得推力，利用百叶窗矢量排气装置实现升力/推力切换。但由于排气装置导叶的联动特性，排气面积会随着导叶的偏转而逐渐变化。这可能会对系统造成不确定的影响。此外，考虑到推进系统的开发成本，需要根据系统特点明确核心涡扇是否需要重新设计。更多，推进系统的过渡性能（VTOL 到飞行）也需要研究。为此，本研究结合核心涡扇的特点，建立了气驱风扇推进系统的整体模型，对这些问题进行了分析。结果表明，百叶窗式矢量排气装置可以很好地匹配气驱风扇推进系统。并且当推进系统组成时，气驱风扇不会显着影响核心涡扇的运行特性。此外，初步分析表明，气驱风扇推进系统能够满足固定翼垂直起降飞机过渡状态的功率需求。并且推进系统的特性可以使固定翼VTOL飞机的起飞推重比要求低至1.1。