叶片弯掠对多级风扇气动性能的影响

利用数值模拟的方法,研究了多级环境中叶片弯掠对风扇整体气动性能的影响。研究过程将弯、掠叶片分别应用于某三级风扇的第二、三级静叶,以对比性能变化并研究其内在的流场作用机制。结果表明,多级环境中弯掠叶片排可通过改变沿径向密流分布对其它叶排施加影响;弯和掠都能借助低能流体迁移控制端壁流动,但掠叶片同时具有对主流的迁移作用,这就使得掠叶片对沿径向密流分布的影响要大于弯叶片;随转速下降,弯叶片的流体迁移作用被增强,掠则相反。此外发现,在多级环境中单独使用时可获得性能改善的弯掠叶片,组合应用后并未获得双重的性能收益。

Effects of swept-curved blade on the performance of the multistage fan

Numerical simulations were carried out to investigate the effects of swept-curved blade on the performance of the multistage fan.Swept and curved blade were applied to the 2nd and 3rd stator of a three-stage fan to study the mechanism of performance improvement.The results show that swept-curved blade row can affect the others by changing the velocity density distribution along blade height.Swept blade can move not only the end-wall low energy fluid which is similar with the curved blade,but also the main flow fluid.Thus,the swept blade influence on velocity density distribution is greater than the curved blade.As the speed of rotation decreases,the effect of fluid migration of the curved blade is strengthened,whereas the swept blade is opposite.It is found that,the combination of curved and swept blade,which are all effective on improving the performance when used individually,can not get the double profit in performance.