非均匀间隙下进气畸变对风扇性能的影响

引入真实进气道的进气总压畸变,分析了偏心形式周向非均匀间隙下,畸变区相对位置对风扇流场的影响。结果表明,畸变流的影响总滞后于进口畸变位置,滞后角约为90°,在原有非均匀间隙流场中最恶劣的流动位置附加畸变流,对风扇性能的影响是最大的,且旋转失速与周向间隙收敛扇区的流动密切相关,推断一旦从大间隙到小间隙过程中无法将叶尖高熵溢流耗散,风扇转子将进入失速。

Effects of inlet flow distortion on fan performance under nonuniform tip clearance

Based on the real total pressure distortion, the influence of relative position of inlet distortion on fan flow field under nonuniform clearance was studied. The results showed that there was a phase lag between the rotor flow filed and the inlet flow distortion, which was about 90°. The total pressure distortion resulted in the most remarkable effect when it acted at the circumferential position with the worst flow of the original flow field, and the rotating stall was closely related to the sector with convergence clearance. It can be inferred that the stall will occur once the overflow with high entropy has not been dissipated during the propagation from large to small clearance region.