Effect of Inlet Air Pre-Cooling of Water Injection on Compressor Performance at High Flight Mach

In high altitude and Mach number, the inflow air with the high temperature will influence on the aero-engine performance while the mass injection pre-compressor cooling (MIPCC) technology is one of the problemsolving ways to reduce high temperature. To explore the convection coupling process between droplet and inflow air, the compressible Reynolds average N-S equations in the compressor coupled with the pre-cooling section is solved by the finite volume method to analyze its performance changes at different water injection rates and droplet sizes. Results show that, in the flight of 3.5 Mach number, the larger water injection rate easily form the shock wave due to the disturbance of droplets in the pre-cooling section. Furthermore, the temperature on the pressure surface near the trailing edge of the rotor blade aggravates along the radial migration, leading to uneven temperature distribution in the radial direction. Within the water injection rates of 0-8% and the particle sizes of 10-20 μm, the inflow mass flow of air improves by 15.3-31.4%; the temperature ratio of compressor drops by 3.6-16.14%, which results in the decrease of specific compression work of the compressor and the changing trend from “increasing” to “decreasing” for the compressor efficiency.