真实进气条件下发动机稳定裕度损失评估

Assessment of Stability Margin Loss of Aeroengine under Actual Inlet Condition

关键词:  航空发动机  试飞数据  稳定裕度损失  总压畸变  平行压气机模型  稳定边界

Key words:  Aeroengine  Fight-test data  Loss of stability margin  Total-pressure distortion  Parallel compressor model  Stability boundary

摘要:

为了确定航空发动机压缩系统在进气总压畸变条件下的稳定裕度损失，开展了基于平行压气机模型的稳定裕度损失评估方法研究。通过对试飞中实测的总压畸变图谱进行等效转换，转换结果作为平行压气机模型的输入，得到畸变条件下压缩系统的稳定边界，再通过试飞数据确定压缩系统的流量，从而确定畸变时刻压缩系统的稳定裕度损失。对某型涡扇发动机进行计算，得到周向总压畸变强度为3.3%时风扇的稳定裕度损失为3.8%。通过对两种不同畸变强度的周向总压畸变的计算结果的对比，表明该方法可用于确定总压畸变条件下的稳定裕度损失。

Abstract:

To determine the stability margin loss of the aeroengine compression system under the condition of inlet total pressure distortion， the stability margin loss evaluation method， which is based on the parallel compressor model， was studied. Measured total pressure distortion contour maps in flight test were equivalently converted. Conversion results were the inputs of the parallel compressor model， the stability boundary of compression system was determined under distorted flow. And the mass flow of compression system was determined through the flight test data， then， the stability margin loss of compression system can be calculated at distorted time. For a turbofan engine， the stability margin loss of the fan is 3.8% when the circumferential total pressure distortion intensity is 3.3%. The comparison of the calculated results of different intensity of circumferential total pressure distortion shows that the method can be used to determine the stability margin loss under total pressure distortion.