两级跨声风扇气动性能的实验和数值模拟

Experimental research and numerical simulation were conducted on a two-stage transonic fan. Both two rotors of the two-stage fan adopted the forward-swept design, and the last stage stator employed a tandem configuration. Experimental measurements of characteristic parameters were conducted at different rotation speeds. Then, steady numerical simulations of the fan were conducted at 100% rotation speed and 80% rotation speed using the Spalart-Allmaras (SA) turbulence model and the SA-Helicity turbulence model. Results indicated that the SA model underpredicted the stall margin, while the SA-Helicity model significantly improved the prediction accuracy of the stall margin, the efficiency, and the pressure ratio. The loading subjected by the second stage was higher than that by the first stage. The second stage primarily contributed to the increase of total temperature and pressure as the operating condition moved towards the near-stall point. The shock wave and the corner separation constituted the primary sources of loss. In the near-stall condition, a large corner separation at the first stator and the first row of the stage tandem stator was the main reason for the increase of losses.