Geometrical influence on downstream centrifugal impeller inlet distortion in an axial-radial combined compressor

摘要

Numerical simulation for the flow field is conducted on an axial-radial combined compressor to investigate the influence on the inlet flow angle of the downstream centrifugal impeller blade with the identical/uneven moving blade number and the variation of the clocking position effect. The result shows that, the superposition phase of the two factors at the impeller leading edge fluctuated with changing impeller blade number and rotor clocking position. When the moving blades are different at the upstream and downstream, with two superposition phases appearing at the leading edge of the impeller, the amplitude of inlet flow angle fluctuate heavily. When two rows' moving blades are the same, with only one superposition phase appearing at the leading edge of the impeller, the amplitude of inlet flow angle varied uniformly. The relative superposed phases have great influence on the inlet flow angle of the downstream centrifugal impeller blade, while the combined compressor with identical number of moving blade at different clocking positions.