Abstract: In order to have a detailed understanding of distortion effects on intermediate duct， a set of evaluation parameters for intermediate duct were proposed， and research of distortion effect based on these parameters was conducted on a small turbofan intermediate duct to study the mechanism of distortion development. The results showed that with the expansion of inlet distortion range， distortion of the outlet is gradually weakened compared with the inlet， in some cases the distortion can be reduced. Compared with inlet flow， outlet low total pressure area of casing shrinks， and outlet low total pressure area of hub expands. While the inlet low total pressure area of casing expands， the outlet distortion near hub will be strengthen. While the inlet low total pressure area of hub expands， the outlet distortion near the hub will be weaken.

Key words: Compressor;Intermediate duct;Evaluation of distortion effect;Flowfield distortion;Distortion transfer

摘要： 为深入了解中介机匣畸变效应，提出了一组中介机匣畸变效应评估参数，并基于提出的评估参数，对小型涡扇发动机中介机匣进行了畸变效应研究，分析得到中介机匣对于流场畸变的作用机理。研究结果表明：随着进气畸变范围的增大，中介机匣出口畸变程度相比进口的放大程度逐渐减弱，甚至出现畸变程度缩小；出口流场与进口流场相比，靠近上环壁的低总压区范围减小，靠近下环壁的低总压区范围则会放大；进口流场在上环壁附近的低总压区范围的增大，将恶化出口流场在下环壁附近的畸变程度，而进口流场在下环壁附近的低总压区范围的增大，则会改善出口流场在下环壁附近的畸变程度。

关键词: 压气机;中介机匣;畸变效应评估;流场畸变;畸变传递