Topological characterization of vortex structures on a transonic compressor stator during the stalling process

Abstract

Numerical simulations, verified against experimental results, were used to study the stalling process of a transonic compressor. The method of topological analysis was used to study the distribution of the flow field on the blade surface in detail. In this manner, the steady three-dimensional vortex structure of the transonic compressor stator under transition conditions was established, and the mechanism of the stalling process was revealed from the perspective of the vortex structure evolution. The results show that in the process of stalling, as the back pressure increases, the separation areas on the suction side of the stator and the scale and strength of the separation vortex also increase, thereby weakening other vortices and causing a large amount of low-energy fluid to accumulate in the passage. Thus, the passage is blocked, and the through-flow capability of the compressor is reduced. In addition, because of the complex movement of the vortices and the transport of low-energy fluid clusters, the boosting capacity of the compressor is reduced, thus causing the compressor to stall.