摘要
通过改变前缘几何形状来分析其在设计攻角、非设计攻角下前缘附近的流动机理.研究结果表明:在宽工况范围内椭圆型前缘表现出了较优越的性能,不但在设计攻角下能很好抑制吸力峰的强度以避免前缘分离泡的产生,而且在较宽的攻角范围内都能保证前缘附近边界层状态基本不变.当正攻角很大时,不同前缘形状前缘附近都会出现分离泡,且会诱导边界层发生转捩,但椭圆型前缘边界层开始发生转捩的攻角会向大攻角方向移动.在20°攻角下,椭圆型前缘叶型的损失相比基准叶型下降了7%左右.进口湍流度的增加不会改变吸力峰的强度但可以减弱前缘分离泡的强度.
A research on the flow field around leading-edges of different geometries at design and off design incidence was done. It is found that the elliptical leading-edge exhibits better performance, since the elliptical edge can not only depress the pressure spike to suc cessfully avoid the presence of separation bubble near the leading-edge in wide range of working condition, but also keep the boundary layer almost unchanged small in wide range of inci dence. When the positive incidence is large, the separation bubble will emerge at the leadingedge of different shapes, inducing the boundary layer transition, however, the research shows that the elliptical leading-edge will bring about the boundary layer transition at larger incidence. The elliptic leading-edge blade decreased about 7% of profile loss compared to baseline blade profile at the insidenee of 20°. The increase of the inlet turbulence intensity could depress but not completely suppress the separation bubble at leading-edge.
出处
《航空动力学报》
EI
CAS
CSCD
北大核心
2014年第6期1482-1489,共8页
Journal of Aerospace Power
基金
高等学校博士学科点专项科研基金(20101102110011)
关键词
涡轮
前缘形状
吸力峰
分离泡
边界层
湍流度
turbine
leading-edge geometry
pressure spike
separation bubble
boundary layer
turbulence intensity
