BVF在吹气控制压气机叶栅分离流中的应用

BVF application on blowing control of flow separation of a compressor cascade

结合边界涡量流(BVF),对叶片开缝吹气的方法控制扩压叶栅流动分离进行了数值模拟.结果表明,叶片开缝可有效的吹除附面层内的低速气流,从而弱化或消除流动分离,提升性能.对叶栅开缝位置、开缝角度及缝隙宽度等影响因素的组合研究,获得了最佳开缝方案.BVF气动分析显示,叶片吸力面上高的BVF正峰值是大尺度分离发生的预兆,最佳开缝位置在BVF正峰值之后,分离点前后的一段区域,通过选择合适的位置,可取得在最大工况范围的最佳效果.

Controlling flow separation with blowing-slot was simulated numerically on a 2-D cascade in collaboration with boundary vorticity flux（BVF）. The results show that steady blowing can take away the slow airflow of the boundary layer, the separated flow is controlled and the performance of cascade is greatly improved. By means of investigation on the cascade performance variation with slot position, blowing angle and slot width, the best slot scheme is obtained. BVF aerodynamics analysis indicates that the high positive peak of BVF is a sign of large scale flow separation, BVF distribution and cascade performance are interrelated, the blowing can adjust BVF distribution well to improve the performance. The best slot position is located behind the positive BVF peak and in a small zone near separation point. By selecting an appropriate slot position, the best effect could be obtained in a wide operating range.