直孔射流对压气机叶栅流场影响的实验研究

为了探究直孔射流对压气机叶栅的影响,通过实验方法,结合流场显示技术和流场测试技术,对无控叶栅和直孔射流方案下的压气机平面叶栅在正攻角下的流场结构和气动性能进行了分析。结果表明:无控叶栅中吸力面存在三个螺旋点,而不同射流方案下螺旋点的数量和位置变化明显;无控叶栅端壁存在一个从吸力面起始的分离区,布置射流孔后,在射流孔前发展出马蹄涡,马蹄涡的两个分支的发展情况及其对流场影响随着不同射流方案呈现出不同的特点;射流孔的位置对控制效果有明显的影响,最佳方案减小了3.2%的总压损失,增大了1.86%的通流流量;在最佳方案下,吸力面螺旋点数量减少到了1个,端壁没有明显的尾迹出现,出口处高损失区的欠偏转和端区的过偏转均有所减弱。

Experimental Study for Effects of Straight Jets on Flow Field Structure in a Compressor Cascade

Experimental study was used with both flow field visualization methods and aerodynamic parameter measurement methods to understand the flow structure and aerodynamic performance of a linear compressor cascade of both original case and the cases with excitation jets under positive attack angle. The results support the following conclusions. Three spiral nodes appeared on the blade suction surface under the original case without excitation, while the number of spiral nodes and the position of the nodes differed among the cases with excitation jets at different jet hole position. A separation zone that originated from the blade suction side existed on the endwall under the original case without excitation. With the arrangement of the excitation jet, horse shoe vortex appeared before the jet hole on the endwall. The development of the branches of the horse shoe vortex differed with different excitation schemes and showed different influences on the flow field structure. The excitation jet hole position played an important role on the management of the corner separation. The optimum case reduced the total pressure loss coefficient by 3.2% and increased the passage mass flow rate by 1.86%. Meanwhile, the number of spiral nodes on the blade suction surface was reduced to one and no wake was observed on the endwall. The over-turning near the endwall and the insufficient turning in the high loss zone were also weakened.