弹用涡扇发动机气动稳定性计算与评定

Computation and assessment of aerodynamic stability of turbofan engine for missile

介绍了弹用涡扇发动机气动稳定性计算的基本方法和评定流程。给出了进气畸变、附加功率提取、附加引气、加速过程对弹用涡扇发动机气动稳定性影响的计算分析模型。其中, 进气畸变对发动机气动稳定性影响的计算采用平行压气机模型, 基于李亚普诺夫理论的方法完成; 附加引气、功率提取对发动机气动稳定性的影响采用通过对发动机转子间质量、动量、能量守恒方程进行修正的方法进行; 加速过程对发动机气动稳定性的影响采用欧拉方法求解动态的质量、动量、能量守恒方程的方法完成; 最后采用“层叠”的方法进行各种降稳因素的综合评估。通过比较可以看出, 进气畸变是弹用涡扇发动机主要的降稳因素。

A basic method and flow chart was presented for assessment of aerodynamic stability of turbine engine for missile. The considered factors decreasing surge margin of turbine engine consist of inlet distortion, power extraction, additional bleed and acceleration. A quasi one-dimensional, time dependent system model based on the parallel compressor theory was used to compute the effect of inlet distortion on turbine engine stability; Through Modifying steady state continuum equation, momentum equation and energy equation, the effect of power extraction and additional bleed on turbine engine running line was computed. Unsteady state continuum equation, momentum equation and energy equation were solved for computing the effect of acceleration on turbine engine running line. At last, cumulative method was used to synthetic assessment of the effect of all decreasing factors on turbine engine stability.