Analysis of the coupled flow through axial skewed slots casing treatment and rotor passage

Axial skewed slot casing treatment is known as a powerful method to improve the stall margin of compressor. A time accurate 3-dimentional numerical simulation of the coupled flow through a subsonic axial-flow compressor rotor passage and axial skewed slots casing treatment was presented in this paper. The numerical results agreed well with experimental test data for estimation of the global performance. The different tip flow topology of the compressor rotor with axial skewed slots casing treatment and the unsteady interaction between rotor passage and axial skewed slots casing treatment were detailed analyzed. The numerical results showed that the control of the high loss, high blockage tip leakage flow and its vortex is the basic mechanism which are responsible for the stabilizing impact of casing treatments.