Secondary flow and loss mechanisms of variable stator vanes in an annular cascade

Axial compressors with variable stator vanes require annular gaps and radial from the endwalls for smooth adjustment, which induces complex secondary flows such as penny leakage vortex tip vortex, leading to a negative impact on aerodynamic performance. To better understand these mechanisms, numerical investigations were conducted four different clearance configurations. The results show that moves toward suction side under transverse pressure gradient mixes hub corner stall vortex. This causes separation be further developed, an increase in total loss by 13.6%. However, flow could reduce gradient, prevents mixing low-energy fluid region. Moreover, is also replaced effectively suppresses range of separation. Under comprehensive effects coefficient increased only 7.6%. Therefore, effect between main reason higher production cascade, findings provide theoretical support future application control technology loss.