Mechanism Research Of Total Pressure Distortion Effects On The Flow Strueture In A Supersonic Compressor

This paper is a presentation of a numerical simulation study on one stage axial flow compressor which is supersonic and high loaded. As the inlet distortion is closely related with the performance and the stability of compressor, it could deteriorate the aerodynamic performance of the compressor, decreases the efficiency and debases the stability margin,induse the appearance of rotating stall or surge. So the research of distortion have great significance. Applying the unsteady full-annulus simulation, the key point is how inner flow field of the rotor and stator response to the different inlet total pressure distortions in design condition.The object of study is the modification of one stage compressor. Therefore parameters are changed from the original one. So we need to redraw the characteristic curves. This paper mainly draw the characteristic curves under 90%,100%and110% of designed speed. These curves are simulated by Fluent and Numeca (two different softwares). Thus the results about software independence are proved. Employing the adaptive mesh refinement function to adapt the grid, the grid independence is proved from the general parameters and inner flow field of key sections.The marked single passage is used to investigate the unsteady simulation. First, the distortion that insert-board depth is 38.2% of inlet radius is deeply studied. The results are showed that the time averaged mass flow rate and efficiency of compressor are decreased, the available stability margin are reduced. Via the study of flow field in each time step of one period, the response mechanism between inlet distortion and inner flow field is emphatically revealed. In the rotor flow field, the variation of shock structure, intensity and position under effect of distortion is analyzed in detail; in the stator flow field, the separation law of stator end-wall is studied. What’s more the causation is explored profoundly.Via the studied about different deepness of insert-board distortions, indicated that with the increasing of the deepness, the time-averaged mass flow rate and efficiency of compressor are both decreased. The flow separation of stator mainly concentrate in the end-wall, the separation in stator hub will suppress the separation in casing area. Once the depth increased to definite value, the deeper insert-board reach, the more full development separation passages increase. But the degree of deterioration would not become more serious in those separation passages. To the compressor this paper studied, the distortion near the flange impacts the efficiency of the compressor closely,while that near the hub impacts the mass flow rate closely.