涡扇发动机地面起动过程性能模拟

用积分方法建立了混合排气加力涡扇发动机起动过程模拟模型并用该模型进行了仿真计算,模型基于气动热力学方程、各部件特性以及经验关系式,根据给出的发动机起动过程初始条件、燃烧室供油规律等进行计算.为说明所建立的起动性能模型的模拟效果,将程序计算结果与试验结果进行了比较,结果表明该起动仿真模型能较准确地模拟混排加力涡扇发动机的地面起动过程.还分析了计算过程中对起动过程有比较大影响的因素,包括计算时间步长,起动机脱开转速,燃烧室总压恢复系数的经验系数,大气温度、压力以及海拔高度等.了解这些因素对起动过程及模拟结果的影响,便于通过修正的途径将该计算方法用于发动机地面起动性能的准确模拟.

Model for ground starting of turbofan engine

The simulation model of turbofan engine for ground starting was described.The simulation is based on thermo-aerodynamics relationship,the components' characteristics,experienced formulas.According to being given known condition and fuel regulation,the starting has been simulated by integral method.In order to show the effect of the simulation,the results of the simulation model calculated have been compared with the testing results.The compared result shows that the simulation model can simulate mixed flow turbofan engine with afterburner for ground starting effectively.These parameters and coefficients have been analyzed,including calculating time interval,the rotation speed of the starter off,experiential coefficient of combustion total pressure recovery coefficient,the environment temperature and pressure,the airport attitude.The results show that these parameters and coefficients have significant effect on ground starting simulation.