掺混系数对航空发动机整机稳定性影响研究

Investigation of Mixture Coefficients in Numerical Simulation of Aeroengine Stability

良好的飞机推进系统要求航空发动机在整个飞行包线范围内都必须有足够的可用稳定裕度,这就决定了航空发动机整机稳定性数值模拟的重要性。为使航空发动机整机稳定性数值模拟计算结果精确度更高,在常用的一维稳定性数值模拟计算模型中加入掺混系数,使得模型能够模拟航空发动机轴向单元体中轴向单元之间的能量交换和动量交换,且对掺混系数对数值模拟结果的影响进行分析研究。结果表明,畸变衰减主要是由风扇和压气机单元引起;风扇和压气机部件单元体的掺混系数对稳定性影响很大,压缩部件附近一般单元体掺混系数对稳定性影响有限。

The health engine requires enough stability margins in all flight envelopes, which decides the impor- tance of the numerical simulation of aeroengine stability. In order to make the engine stability numerical simulation results in higher accuracy, the numerical simulation of aeroengine stability model draws into the mixing coefficients, so that the model can simulate the aeroengine axial unit in the circumferential direction of energy exchange and mo- mentum exchange between units. The investigation of the mixing coefficients on the numerical simulation has been done. The results show that the distortion attenuation is mainly caused by the fan and compressor unit ; meanwhile the mixing coefficients of fan and compressor unit have great effect on the aeroengine stability, while the mixing coeffi- cients near the unit of fan and compressor have limited impact on the aeroengine stability.