Effect of forward swept blade on transonic high pressure ratio centrifugal compressor under different conditions

A transonic centrifugal compressor with high load and high pressure ratio is adopted as the basis of this study. The influence on the internal flow field of high-load centrifugal compressor is studied by forward-swept design of the leading edge of the main blade. Four schemes with different forward sweep angles α (5°, 10°, 15°, 20°) are numerically simulated and comparatively analyzed. By analyzing the performance of the design point, the highest efficiency point and the near-blocking point, the flow law of the internal flow field of the compressor is studied. The results show that the leading edge forward sweep of the main blade has certain advantages in improving the flow capacity and stall margin of the compressor compared with the non-forward sweep reference. Under the design condition, the compressor performance is improved when the forward sweep angle is 10°, in which the efficiency is increased by 0.379 % and the pressure ratio is increased by 1.84 %. In addition, the forward sweep angle shows a consistent improvement in the degree and intensity of low-energy fluid accumulation downstream of the impeller channel under blocking conditions.