带不同形状吸力面小翼的压气机叶栅变间隙实验研究

Experiment on Variable Tip Clearance Characteristics of Compressor Cascade with Different Shapes of Suction-Side Winglets

关键词:  吸力面小翼  压气机叶栅  泄漏涡  间隙流动  泄漏损失

Key words:  Suction-side winglet  Compressor cascade  Leakage vortex  Clearance flow  Leakage loss

摘要:

为了控制和降低压气机中由叶尖间隙引起的泄漏损失，对加装不同形状的吸力面小翼变间隙流场进行了实验研究。通过五孔探针测量叶栅出口流场，详细分析了不同间隙下吸力面叶尖小翼对压气机叶栅出口流场结构、气动损失和通流能力的影响。结果表明:与常规叶栅相比，附加吸力面小翼的叶栅泄漏涡涡核向远离叶片吸力面移动，且强度明显减弱，泄漏涡的起始点转移到吸力面小翼的最大厚度轴向位置处。不同形状的吸力面小翼在大间隙高度下对叶栅损失的影响较为明显，其中SW25方案叶栅在3%h间隙高度下效果最佳，可使叶栅出口总压损失降低15.38%。研究的三种不同形状的吸力面小翼仅在小间隙高度下改善了叶尖泄漏涡造成的叶栅出口气流角的过偏转/欠偏转现象。

Abstract:

In order to control and reduce leakage loss in the compressor caused by the tip clearance， detailed experiments have been carried out on variable tip clearance flow with different shapes of suction-side winglets. And the outlet flow fields of the cascade were obtained by the five-hole probe， the effects of suction-side winglets on outlet flow field structure， aerodynamic loss and the flow capacity of the cascade were detailed analyzed under different gaps. The results show that compared with conventional cascades， leakage vortex core of the suction side winglet cascades moves away from the blade suction surface， and the intensity is significantly reduced， the starting point of leakage vortex moves to the maximum thickness of the axial location. Effects of suction-side winglets with different shapes in large tip height on cascade loss are more obvious， and the SW25 scheme cascade under 3% clearance height is best， which can reduce cascade outlet total pressure loss by 15.38%. The underturning and overturning of outlet flow angle induced by leakage vortex are reduced only in smaller tip height.