Passive Control via Slotted Blading in a Compressor Cascade at Stall Condition

This paper was conducted to explore the potential of passive control via slotted bladings in linear cascade configurations under stall condition. Through an extensive 2D-numerical study, the effects of location, width and slope of slots were analyzed and the best configuration was identified. Based on the optimal slot, the 3D aerodynamic performances of cascade were studied and the influence of slotted blading to control endwall flow was investigated. Both 2D and 3D calculations are performed on steady RANS solver with standard k-epsilon turbulence model and low Mach number regime. The total loss coefficient, turning angle and flow visualizations on the blade and end-wall surfaces are adopted to describe the different configurations. The obtained results show, for 2D situation, that a maximum of almost 28% reduction in loss coefficient had been reached and the flow turning was increased with approximately 50. Concerning 3D flow fields the slots marked their benefit and delays the boundary layer separation on both end wall and blade suction surface at mid span.