尾流撞击效应在低速轴流压气机中应用实验研究的初探

通过改变尾流撞击效应扰流耦合器的叶片数目来改变尾流撞击效应的激励频率,从而研究其对压气机稳态性能的影响。通过12组方案的实验,当尾流撞击频率为2 000 H z和4 000 H z时,对压气机失速裕度的改善最为明显,相对增量分别达到19.5%和15.2%;当尾流撞击频率为1 000 H z时压气机性能有所恶化。并得到转子的分离流特征频率约为2 000 H z。也就是说,激励频率为特征频率及其倍频时流场可获得最好的气动性能,而激励频率为特征频率的1/2时流场的损失最大。此外,初步讨论了尾流撞击效应作用机理及激励频率与性能提高的关系,这就为轴流压气机中两种流态转化的工程应用,特别是多级轴流压气机设计中的级间匹配问题提供了一个新的思路与途径。

Applied Study on a Low Speed Axial Compressor with Wake Effects

In this thesis,the blade number of wake effect disturbance coupling was changed in order to vary the exciting frequency of wake effect.In this way,the influence of exciting frequency on compressor steady state performance was studied.Through 12 wake effect disturbance coupling experiments,the stall margin was improved significantly at the wake effect frequencies of 2 000 Hz and 4 000 Hz,and the relative increase of surge margin reached 19.5% and 15.2% respectively.However,the exciting frequency of 1 000 Hz worsens compressor performance.The characteristic frequency of flow separation in rotors wake is about 2 000 Hz.That is,the optimal performance is achieved when the exciting frequency is exactly the characteristic frequency or its multiples.The performance is the worst when the exciting frequency is half of the characteristic frequency.Furthermore,the principle of wake effect,and the relation between stimulation frequency and the improvement of compressor performance was studied in a primary stage.This offers a new idea and method to the application of the conversion of two flow types in axis-flow compressor,especially to the matching in the design of multistage axis-flow compressor.