燃气旋流和湍流强度对转静盘腔入侵及流动特性影响的数值研究

In order to investigate the influence of mainstream swirl and turbulence on the gas ingestion rules and mechanisms in the rotor-stator cavity, this study conducted numerical simulations of the influence of three different operating conditions including mainstream swirl angle (SA), turbulence intensity and the combined effect of swirl and turbulence on the gas ingestion rules under a fixed sealing cold air mass flow. The results reveales that when only swirl exists, the distribution position and scale of the Batchelor flow core within the cavity are directly affected by the mainstream swirl angle, meanwhile, the flow characteristics of the core also cause significant changes in the sealing efficiency; additionally, the swirl angle affects the gas ingestion downstream by influencing the pressure distribution upstream of the sealing outlet. When there is no swirl angle and the mainstream turbulence intensity changes, under the condition of extreme turbulence intensity / = 20%, the Batchelor core on the stator side almost disappears, and the disc cavity suffers severe gas ingestion. When the mainstream turbulence intensity / is fixed at 20%, and the swirl angle acts together with it, the ingestion is alleviated compared to SA =0°, but the sealing efficiency under the condition of SA =15° is slightly lower than that under SA =30°. This is mainly because the pressure distribution upstream of the sealing outlet exhibits different fluctuation characteristics under the coupled action of turbulence and swirl.