叶片弯曲对大折转压气机叶栅内分离结构的影响

通过数值模拟,分析了叶片周向弯曲对大折转角压气机叶栅内分离结构的影响。弯角分别为±10°,±20°,±30°。应用壁面流谱的拓扑法则,详细讨论了不同弯角下的分离形态。结果表明,正弯可以有效遏止角区分离,改变吸力面的分离形态,但不能完全消除吸力面的分离。因此一定范围内的叶片正弯可以改善流动,但当弯角大于20°时,流动重新恶化。反弯则使得叶栅内分离趋势增加,气动性能明显降低。

Effect of bowed blades on the separation structures in high-turning compressor cascades

A numerical simulation was performed to analyze the effect of bowed blades on the separation structures in a high-turning compressor cascade.The bowed angles were ±10°,±20°,±30° respectively.Using the topological rules of the surface flow pattern,the separation configurations on the suction surface at different bowed angles is discussed.The results show that a positive bowed blade can restrain the corner separation and change the separation configuration,while it can not avoid the flow separation on the suction surface.So,although a positive bowed blade with a small angle can improve the flow performance,the flow becomes worse again when the positive bowed angle exceeds 20°.A negative bowed blade increases the flow separation and the flow performance is reduced remarkably.