Aerodynamic and thermodynamic analysis of an aero-engine pre-swirl system based on structure design and performance improvement

As a vital part of the pre-swirl air supply system, the rotating receiver hole will affect the cooling air quality supplied to turbine rotor blades of an aero-engine. It is concerned about the influence mechanism of the receiver hole on system performances. Thus, novel theoretical relations are proposed about the effect of both the mass flow rate ratio and rotating Mach number on the system pressure ratio, temperature ratio and temperature drop efficiency. Then, a comparative analysis is carried out to guide the structure optimization of the receiver hole through numerical methods with experimental verifications. Especially, a high-speed test rig is conducted to comprehensively evaluate the optimal rotating receiver hole about the system aerodynamic and thermodynamic characteristics. Numerical results show that the vane shaped receiver hole has the best system performance relative to both runway shaped and drilling shaped structure. The circumferential angle of the receiver hole can significantly reduce the system specific power consumption. Based on pressure and temperature measurement in the test rig, the vane shaped receiver hole can obviously improve the system performance, resulting in 13% increase in system temperature drop efficiency and 28% decrease in dimensionless system specific power consumption. Research conclusions can provide reference to enhance the pre-swirl system performance by optimizing design of the receiver hole.