Numerical investigation on the aerodynamic performance and flow mechanism of a fan with a partial-height booster rotor

Abstract To further improve the thrust-to-weight ratio of turbofan engines, the flux capacity and core pressurization capacity of the fan should be enhanced. In the current study, detailed investigations are conducted to detect the effects on the aerodynamic performance of a wide-chord transonic fan and the underlying flow mechanism in the fan with a partial-height booster rotor (high-throughflow fan). The results show that the clocking arrangement of the tandem rotor in the high-throughflow fan determines the overall aerodynamic performance. At 20% clocking fraction arrangement ( λ s = 20 %), compared with those of the baseline fan, the mass flow near the choke point (NC) and the total pressure ratio at the peak efficiency point (PE) of the high-throughflow fan are increased by 5.83% and 8.10%, respectively, whereas the casing diameter, peak efficiency, and stall margin nearly remain unchanged, and the increase in the total pressure ratio is mainly attributed to the increase in the core total pressure ratio. This study demonstrates that a high-throughflow fan can effectively improve the aerodynamic performance of the baseline fan, showing great potential in applications.