变循环发动机双外涵匹配研究

针对带核心机驱动风扇的双外涵变循环发动机,提出了1种用于双外涵匹配分析的数值模拟方法。利用计算流体力学Fluent软件对其初步流路进行了研究及优化,在此基础上对双外涵模式流场、不同前涵道引射器状态下的单外涵模式流场进行分析。结果表明:第1外涵道的角度和流通面积对总压恢复系数的影响较大;在由双外涵模式转换到单外涵模式过程中,应将前可变面积涵道引射器开到最大以减小总压损失。该方法能够有效地应用于双外涵变循环发动机流路优化及双外涵匹配分析,为变循环技术的深入研究提供参考。

Study on Double Bypass Matching of Variable Cycle Engines

Aiming at the double bypass matching on a variable cycle engine with coreengine driven fan stage, a numerical simulation method was presented. An initial flowpath of variable cycle engine were analyzed and optimized by a CFD sofiware Fluent. The flow fields of double and single bypass mode with different front variable area bypass injectors were analyzed. The results show that the angle and areas of the first bypass has observably influence on total pressure recovery coefficient. The front variable area bypass injector should be opened as big as possible to decrease the total pressure loss when shift the double bypass mode to the single bypass mode. The numerical simulation can be used in flowpath optimization and double bypass matching analysis. This study provides a reference for further study on the variable cycle technology.