内 封 严 流 对 预 旋 供 气 系 统 性 能 影 响 的 实 验 研 究

The pre-swirl air supply system plays a crucial role in providing cooling air for the turbine rotor blades in aviation gas turbine engines. To investigate the influence of the inner seal on the pre-swirl air supply system，a high-pressure ratio and high-speed pre-swirl air supply system experimental platform is established. After measurement of 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 air supply system，as well as the system power consumption，temperature drop efficiency，is analyzed. In response to the potential adverse effects of the inner seal inflow on the pre-swirl air supply system，a bypass structure is proposed to divert the inner seal flow. The results indicate that the impact of the inner seal outflow on the pre-swirl air supply system is relatively small，with the maximum variation of the temperature drop efficiency not exceeding 1. 9% under experimental conditions. The inner seal in⁃ flow，on the other hand，can have a significant negative impact on the pre-swirl air supply system. Under the condition of a pressure ratio of 1. 6，the maximum reduction in temperature drop efficiency reached 20. 4% with an increase in the inner seal inflow. The inner seal bypass structure can effectively prevent the mixing of the 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 the inner seal accounting for 15%，the power output of the airflow increased by 37. 8%，and the system temperature drop efficiency increased by 28. 2%.