S弯进气道内附面层抽吸控制对风扇级性能的影响

为了探讨某S弯进气道出口畸变在其后风扇级内的演变过程以及对风扇级性能的影响，在单独对该进气道进行抽吸控制数值研究并优选出最佳方案后，将最佳方案应用到进气道加风扇级的全流道，进而展开全流道数值研究，着重探讨了抽吸控制前后风扇级性能及内部流场结构变化.结果表明:吸气后风扇级整体性能有较大幅度提升，堵塞流量及最大效率分别增加约0.63%和0.57%；进气道出口低能流体在接触转子之前始终聚集在沿程截面底部，所占区域面积沿流向逐渐减小；接触转子至动叶前缘区间内，畸变流体沿动叶旋转方向的相反方向发生偏移，最终覆盖约3个流道；静叶中畸变流体所处流道内的静叶吸力面发生严重的流动分离，且分离主要发生在50%叶高以下，吸气后略有减弱. 

Suction control of boundary layer in S-shaped air intake and its influence on fan-stage performance

To investigate the evolution process of an S-shaped air intake exit distortion as well as its influence on the downstream fan-stage performance, a series of suction control for the single air intake were carried out at first. And then the best suction solution was selected and applied to the whole structure numerical simulation. Results show that the choked mass flow and the maximum efficiency of the fan-stage increase about 0.63% and 0.57% respectively after suction. In addition, the low energy fluid gathering at cross section bottom decreases ceaselessly as it gets to the tip station of the rotor hub. Since it attaches the tip of the rotor hub, the circumferential location of this low energy fluid migrates gradually along the opposite rotation direction and finally covers about 3 flow passages at the rotor blade front edge. Under effect of the air intake flow angle increase caused by the non-uniform air admission and the adverse pressure gradient in the rear part of the flow passage, serious flow separation occurs at the stator blade suction side but mainly exists at 50% span and below and weakens after suction.