双轴涡喷发动机容畸变能力的数值分析

Improved Model for Computing Distortion Compatibility of Twin-Spool Aeroengine

应用建立的改进多子区平行压气机模型，预测了喷水逼喘过程中双轴涡喷发动机主要工作过程参数的变化及容畸变能力．着重分析了不同角度的周向畸变网格引起的进口周向压力畸变对某型双转子涡喷发动机的稳定工作裕度的影响，并与相应的实验数据进行了对比，误差在２％以内，本文为进气道／发动机的匹配试验提供了适用的数值分析方法，应用它可减少试验次数，节省大量费用，缩短发动机研制和发展的周期．

P.R.C. acronautical industry has accumulated much test data on reSI,onse of aeroengincs to intake flow distortion. It now nceds urgently further improving existing simplified models so as to permit computational exploration of situations as yet lacking in test data. This paper attempts to answer this need.NPU (Northwcstcrn Polytechnical University) researches gnvc already simplified models [1,2].These models still contain two shortcomings, which arc essentially: (1) no consideration is paid to that sub-compressor characteristics arc difTerent from test characteristics of comprcssor with uniform intake flow, (2) aerodynamic coupling bctwccn rotors is omitted. It is believed that these two shortcomings are overcome in the model presented in this paper.With the improved model presentcd in this paper, the authors take a certain type of twin-spool engine and compute quantities that are important indicators of distortion compatibility. The authors compute critical distorted angle (test data and computed curve given in Fig.1) and surge margin △Ky and the loss of surge margin ASM, (test data and computed curves given in Fig.3). It can be seen that the improved model gives rather good agreement with test data. SKy and ASM. in Fig.3 are important indicators of stability. The curve relating temperature at turbine inlet to water injection in Fig.2 was predicted with the autbo's simplified model and its trend is found to be in qualitative aprcemcnt with tests conducted later. Befor the tests, there was considerable worry that the temperature at turbine inlet might increase with increasing water injection.