Variation of vortex structure in a compressor cascade at different incidences

Based on experimental results, a numerical study was performed to analyze the flow pattern and the vortex structure in a compressor cascade at different incidences using the topological principles as well as the critical principles of the three-dimensional separation. The results show that the topology of the critical points on the suction surface varies with the incidence and that the separation type changes to closed separation from open separation. In addition, the passage vortex is a classical open separation. The horseshoe vortex and the corner vortex belong to closed separation. Finally, the authors propose a new model of the vortex structure in a compressor cascade.