The numerical analysis and experimental research of an aspirated counter-rotating compressor

Domain scaling method was used in the unsteady numerical simulation of a dual-stage counter-rotating compressor. Numerical simulation results show that there exist much high entropy low energy fluids in the tip region on the near stall condition. In order to remove the high entropy flows near the shroud casing and improve the performance of the counter-rotating compressor, the boundary layer removal was conducted on the shroud casing over front rotor (R1) and rear rotor (R2) blade tip region. By shroud casing boundary layer suction, the flow field in the tip area improves greatly and the efficiency of the compressor increases by 0.58%. Based on the numerical results, the boundary layer suction system and measurement platform were established afterwards. The experiment was carried out with 0.9% relative suction rate in R1 and R2 tip region shroud casing respectively at 70% corrected rotating speed. Experimental results also show that shroud casing boundary layer suction can improve the compressor's performance effectively on the small flow rate conditions and has a positive role to enlarge the stable operating range.