Abstract: The core driven fan stage (CDFS) is one of the key components for the double bypass variable cycle engine. A methodology called CDFS matching map for the CDFS matching in the off-design operating mode,the double bypass mode, was established using velocity triangle. The matching map describes the operating characteristics and the variations of the main aerodynamic parameters of the CDFS in the double bypass mode. For a given mass flow rate and reduced pressure ratio of the CDFS in the double bypass mode, the rotation speed needs to be reduced to keep the rotor inlet relative flow angles unchanged. Given the mass flow rate and pressure ratio in the double bypass mode, the rotor inlet relative flow angles decrease if the rotation speed increases in the double bypass mode.

Key words: Double bypass variable cycle engine; Core driven fan stage; Velocity triangle; Matching methodology

摘要： 核心机驱动风扇级(CDFS)是双涵道变循环发动机的关键部件之一。为了开展CDFS在非设计模式下(双涵道模式)的匹配分析,利用速度三角形建立了CDFS在双涵道模式下的匹配特性图,该图能够正确反映双涵道模式下CDFS的工作特点和主要气动参数的变化趋势。结果表明:给定CDFS在双涵道模式下流量时,随着压比下降,需要降低CDFS在双涵道模式下的转速才能保证转子进口相对气流角不变；给定双涵道模式的流量和压比时,若要使转子进口相对气流角下降,需要增加CDFS在双涵道模式下的转速。 

关键词: 双涵道变循环发动机;核心机驱动风扇级;速度三角形;匹配方法 