Effect of Load Distribution at the Roots among Stages on Performance of a High Bypass-ratio Fan/Booster

The modern high-performance aero-engines have raised higher requirements on the fan/booster, such as high through-flow, high pressure ratio, high efficiency and a wide range of stable operation. In this paper, a method called arbitrary camber lines blading design method for both axial and centrifugal compressors and three dimensional CFD (computational fluid dynamics) calculation are used to design and analyse the results of the aerodynamic design of a high bypass-ratio fan/booster. By changing load distribution on the roots among the rotors, the flow of the fan/booster can be affected. The results of the study show that increasing the load on upstream stages roots can help relieve the separation at the roots of the downstream stages, which leads to the increase of the total pressure, adiabatic efficiency and stall margin of the core duct of the fan/booster.