变循环发动机建模方法研究及验证

研究了变循环发动机(VCE)关键部件建模技术.采用叶尖叶根分段建模技术建立了两段风扇的数学模型,使之更适用于VCE.基于流场分析,建立了活门开度、外涵道进口总压、动压与外涵道总压恢复系数之间的智能映射,完善了外涵道模型.建立了VCE部件共同工作方程,获得了VCE部件级数学模型.基于欧洲空间与推进系统仿真数据库进行设计点计算,并开展了仿真验证.仿真结果表明:建立的数学模型表现出的工作性能与实际发动机实验结果一致,在低马赫数下双外涵道模式推力更大、耗油率更低;相反在高马赫数下单外涵道模式推力及耗油率优于双外涵模式,验证了所采用建模方法的有效性.

Research and validation of variable cycle engine modeling method

The key components modeling techniques of variable cycle engine(VCE) were studied. Two fans of VCE were divided into tip and hup sections during modeling process to suit the characteristic of VCE. The relationship between the valve opening, the bypass inlet total pressure, the dynamic pressure and total pressure recovery coefficient of bypass was got based on flow field analysis, and modeled by intelligent network. The co-working equations between components of VCE were set up. Then the component-level model of VCE was got. The bypass model was improved. The design point calculations were completed based on the European Space and Propulsion System Simulation Database, and simulations were carried out. The results of simulations indicate that the mathematical model exhibits the same performance as the actual engine experiment. At low Mach number, the double bypass mode achieves higher thrust and lower specific fuel consumption, and at high Mach number, the single bypass mode shows higher thrust and lower specific fuel consumption. So the modeling method of VCE proposed is feasible.