Axial Compressor Stator Blade Corner Separation And Active Control Technology Research

In recent years,with the further improvement of gas turbine performance requirements,higher requirements have been placed on the single-stage pressure ratio of axial compressors.The development trend of high pressure ratio and high load will inevitably lead to an increase in the reverse pressure gradient in the blade passage,which is more prone to three-dimensional coener separation,and the fact that the inlet distortion causes the deterioration of the compressor flow field and performance degradation cannot be ignored.The research on active control technology of corner separation becomes more and more important.In the practical application of mechanical flow field control of the impeller,compared to setting the suction slot on the rotor,the suction slot of the stator will undoubtedly greatly simplify the suction structure,and can further improve the pressure diffusion capacity of the stator.Aiming at the three-dimensional corner separation of the suction side of a transonic axial flow compressor under the near-stall condition of the stator,firstly studies the effect of the suction slot size and suction volume on the performance and flow of the suction side under uniform air inlet conditions.The best suction scheme SSC1 for the suction surface is obtained,and then the scheme is combined with end wall suction to further study the influence of the combined suction parameters on the suction effect,and obtain the best combined suction scheme EWC under uniform air intake conditions.Finally,based on a detailed analysis of the total inlet pressure distortion flow field,the EWC scheme is applied to the inlet distortion,and the effectiveness of boundary layer suction to control corner separation under distorted conditions is studied.Studies have shown that under uniform air intake conditions,when only suction side scheme is used,the closer the suction slot is to the starting point of the corner separation,the better the control effect of the corner separation,and with the increase of the suction volume,the flow field of the stator is gradually improved,and the performance of the compressor is also improved.For the suction side suction scheme located at the same chord length,the full-leaf high suction can improve the flow field of the stator within the full-leaf height range.The SSC1 scheme located at the trailing edge reduced the total pressure loss coefficient of the stator by 61.7%,and increased the efficiency of stage by 6.9% under 2% suction volume,while the local blade height suction would worsen the blade root flow field.For combined suction of the suction side and the end wall,the suction effect is best when the axial dimension of the end wall suction slot includes the chord length range occupied by the corner separation,and the larger the suction volume,the stronger the control ability.The EWC scheme reduces the total pressure loss coefficient of the stator by 66.3% when the suction side and end wall suction are both 2%,and the efficiency of stage increases by 7.4%.Under the condition of total inlet pressure distortion,combined suction does not significantly improve the performance of the stator under the highest efficiency condition,and deteriorates the flow field in the undistorted area;while the combined suction has better control ability on the corner separation between the distorted and undistorted areas under the near stall condition,and the improvement of the flow field in the distortion zone is greater than that in the non-distortion zone.The suction volume of the end wall has a more significant influence on the corner separation,when the suction volume is 2%,the EWC scheme reduces the total pressure loss coefficient of the stator by 47.2%,and the efficiency of stage increases by 3.8%,compared with the uniform air inlet conditions,the performance of the stator and compressor is slightly reduced.