正/反弯曲对高负荷压气机叶栅流场影响机理

弯曲叶片是改善压气机近端壁流动的有效技术手段之一。为探索叶片弯曲对高负荷压气机叶栅流场的影响机理,在初始高负荷直列叶栅的基础上,设计了不同正/反弯曲水平的叶栅,并采用数值模拟方法对系列叶栅进行研究。研究发现:叶片正弯曲形成了中间静压低、两端静压高的"C"形静压分布,可有效改善压气机叶栅近端壁流场,显著抑制角区分离,使得端壁区域扩压能力提高;正弯曲可增大叶展中部区域负荷,恶化叶中流场,增大流动分离;叶片反弯曲形成了中间静压高、两端静压低的反"C"形静压分布,可显著恶化近端壁区流场,角区分离区增大,端壁区域扩压能力降低,叶中流场有所改善。

Influence Mechanism of Positive/negative Bowed Blade on Highly Loaded Compressor Cascade

Bowed blade is an effective method to improve the near endwall flow field of compressors.In order to explore the influence mechanism of bowed blade on the flow field of highly loaded compressor cascade,the different levels of positive/negative bow cascades are designed and numerically investigated based on the baseline of highly loaded linear cascade.Results show that,positive bowed blade can introduce"C"shaped spanwise static pressure distribution,the near endwall flow field can be improved effectively,the corner separation is eliminated obviously,and the diffusion ability in the vicinity of endwall is increased.Positive bowed cascade can increase the load at mid-span,deteriorate the flow field near the mid-span,and enlarge the flow separation.For the case of negative bowed cascade,opposite"C"shaped spanwise static pressure distribution is introduced,the flow field in the vicinity of endwall is deteriorated significantly,the corner separation is enlarged,and the diffusion ability near the endwall is reduced;on the contrary,the flow field near the mid-span is improved considerably.