Study of the Unsteady Flow Features on a Stalled Wing
Study of the Unsteady Flow Features on a Stalled Wing
复制标题
DOI：
10.2514/2.372
复制
发表时间：
1998
期刊：
影响因子：
2.5
通讯作者：
Steve Yon;J. Katz
中科院分区：
文献类型：
--
作者：
Steve Yon;J. Katz
在小型亚音速风洞中研究了高迎角矩形机翼上失速后流中大型结构的出现。分离流场内的平均和时间相关测量表明，除了机翼失速之外还存在两种不同的迎角状态。浅失速状态在前缘分离开始后立即在狭窄的入射角范围（2-3 度）内发生。在这种情况下，主要的平均流动结构（称为失速单元）表现为模型表面上分离区域的弦向范围内的独特展向周期性，并且可能具有先前未报告的横向移动性。在失速单元内和机翼表面上，发生大幅压力波动的频率远低于钝体脱落的预期，并且对远尾流的影响最小。在深失速状态下，没有观察到失速单元，并且模型附近的分离区域相对没有大幅压力扰动。
The occurrence of large-scale structures in the poststall flow over a rectangular wing at high angles of attack was investigated in a small-scale subsonic wind tunnel. Mean and time-dependent measurements within the separated flowfield suggest the existence of two distinct angle-of-attack regimes beyond wing stall. The shallow stall regime occurs over a narrow range of incidence angles (2-3 deg) immediately following the inception of leading-edge separation. In this regime, the principal mean flow structures, termed stall cells, are manifested as a distinct spanwise periodicity in the chordwise extent of the separated region on the model surface with possible lateral mobility not previously reported. Within the stall cells and on the wing surface, large-amplitude pressure fluctuations occur with a frequency much lower than anticipated for bluff body shedding and with minimum effect in the far wake. In the deep stall regime, stall cells are not observed, and the separated region near the model is relatively free of large-amplitude pressure disturbances.