压气机“修型”叶栅的实验研究

文中通过压气机叶片“修型”叶栅和常规叶栅的对比实验 ,研究了“修型”叶栅栅后三维流动特征。试验结果表明 ,对常规压气机叶片端部尾缘进行局部修型 (即改变叶片的几何形状 ,但与“端弯”方式不同 ) ,在叶栅损失系数基本不变或略有下降的前提下 ,可以有效地改善和控制栅后出口气流角沿叶高的分布 ,以满足下游动叶进口气流方向的要求。平面叶栅试验结果还表明 ,尽管对常规叶栅端部尾缘实施局部修型 ,减小了端区的叶片出口构造角 ,但对整个气流转折角影响不是太大。同时 ,叶栅自身的流通能力基本不受影响 ,甚至有所改善。此技术已成功地应用于多级压气机和喘振裕度的改善、效率的提高以及压气机不稳定脉动压强 (叶片激振动 )和乱分离的抑制

EXPERIMENTAL INVESTIGATION OF AN END-MODIFIED COMPRESSOR CASCADE

A compressor end-modified cascade and its original cascade are compared experimentally to study the three-dimensional flow characteristics at the exit plane of the cascade.The results show that the modification of the end part at the trailing edge of the original blade (which is different from end-bend)would effectively improve the exit air angle spanwise distribution and meet the need of the inlet air angle of next row blades,on condition that the total pressure lose coefficient does not change or decrease.The test results also indicate that although the camber angle of the blades in the end part decreases due to the modification,the paseage-mass-averaged value of the camber angle changes few.Otherwise,the air flow through the cascade is the same to the original or even better.This technique has been successfully applied to improving both stall margin and efficiency of axial multistage compressors and to depressing the unsteady pressure disturbance.