Abstract: In order to design a fuel-injection scheme that could effectively enhance mixing and improve combustion efficiency, in this paper, the structural combination of conical pylon and aero-ramp was studies for the first time, and numerical simulation was carried out upon the cold and hot flow fields of the small pylon/aero-ramp. The experimental results show that:compared with the injection of traditional aero-ramp, the rear injection of multiple pylons in the extended composites can achieve a better mixing effect without causing a large total pressure loss. With the gas generator introduced, the mixing enhancement effect of the pylons is improved significantly. The improved injection scheme can increase the combustion efficiency by approximately 9%. The numerical results can provide certain reference for engineering practice.