Aerodynamic performance of transonic axial compressor with a casing groove combined with blade tip injection and ejection

Blade tip ejection was introduced to a casing groove combined with tip injection in a transonic axial compressor with NASA Rotor 37. A parametric study of compressor performances was performed using three-dimensional (3-D) Reynolds-averaged Navier-Stokes equations with the k-ϵ turbulence model. Effects of three geometric parameters and one operating parameter, i.e., the front and rear lengths and height of the casing groove, and the mass flow rate of groove ejection, on the performance parameters, i.e., the total pressure ratio, adiabatic efficiency, stall margin, and stable range extension, were investigated in the parametric study. The application of a casing groove combined with tip injection and ejection was found to be effective in the simultaneous improvements of adiabatic efficiency, stall margin, and stable range extension without loss of the total pressure ratio of the transonic axial compressor, compared to the case with a casing groove with injection only, and a smooth casing.