Experimental and model investigations of SPS casing treatment on a two-stage compressor

Xu Dong ^a, Letian Zhang ^b, Dakun Sun ^b,*, Xiaofeng Sun ^a

a. Research Institute of Aero-Engine, Beihang University, Beijing, 102206, China
         b. School of Energy and Power Engineering, Beihang University, Beijing, 100191, China

Abstract: This paper will first carry out experimental investigations on a test compressor which is a large-scale, two-stage and low-speed axial one to evaluate the participation of a novel casing treatment (stall precursor-suppressed casing treatment, SPS CT). The compressor performance for its pressure rise characteristics and efficiency are tested and illustrated. Besides, the time-averaged steady and the time-resolved unsteady measurement in this paper finally lead to some further analyses about the stall evolution of this compressor tending to uncover the process of the stall evolution and the mechanism of the SPS CT. The overall performance results indicate that the SPS CT can extend the compressor stall margin by 3%-11% with very limited efficiency loss. And the mechanism for such casing treatment has also been revealed as stall-precursor suppression by observing the evolution of the inception waves. In addition, modeling work have been conducted subject to the effects of SPS CT on the test two-stage axial compressor. The compressor stability model is able to investigate the effects of different geometrical parameters on the compressor stability and then make an optimal design for the SPS CT when it is applied on the test compressor.

Keywords: Axial compressor; Multi-stage; Casing treatment; Stall precursor; Stability model