关键词: 航空发动机, 预旋供气系统, 内封严流, 旁通结构, 实验测量

Abstract: The pre-swirl air supply system plays a crucial role in providing cooling air to the turbine rotor blades in aviation gas turbine engines. In order to investigate the influence of inner seal on the pre-swirl air supply system, a high-pressure ratio and high-speed pre-swirl air supply system experimental platform was established. By measuring parameters such as pressure and temperature at various critical sections of the system, the impact of inner seal inflow and outflow on the pressure and temperature distribution of the pre-swirl system, as well as the system power consumption, temperature drop efficiency, was analyzed. In response to the potential adverse effects of inner seal inflow on the pre-swirl system, a bypass structure was proposed to divert the inner seal flow. The results indicate that the impact of inner seal outflow on the pre-swirl system is relatively small, with the maximum fluctuation of the temperature drop efficiency not exceeding 1.9% under experimental conditions. Inner seal inflow, on the other hand, can have a significant negative impact on the pre-swirl system. Under the condition of a pressure ratio of 1.6, the maximum reduction in temperature drop efficiency reached 21.8% with an increase in inner seal inflow. The bypass structure for inner seal can effectively prevent the mixing of inner seal flow with the mainstream in the pre-swirl cavity, reducing the pressure and temperature in the pre-swirl cavity. Under the condition of a pressure ratio of 1.6 and inner seal accounting for 15%, the power output of the airflow increased by 37.8%, and the system temperature drop efficiency increased by 28.0%.

Key words: aviation engine, pre-swirl air supply system, inner seal, bypass structure, experimental measurement