粗糙带对细长体大迎角流动非对称性的影响

通过模型表面压力分布测量和表面油流图谱显示等试验手段,在低湍流度风洞中探讨了模型头部不同形式的粗糙带对细长体大迎角条件下流动非对称性的影响.结果表明:"条型"粗糙带可以有效改善流动非对称性、降低当地侧向力;"环型"粗糙带可以改善模型表面的分离状态,但是却增强了流动非对称性;"条型 环型"粗糙带对于表面流谱的影响较为复杂.但是这些形式的粗糙带都不能完全消除流动非对称性所产生的侧向力.试验结果还展示出了大迎角状态下,流动非对称性的存在形式与表现特征.

Effects of grit strip on flow asymmetry over a slender revolution body at high angles of attack

By means of such test methods as model surface pressure distribution measurements, skin oil pattern visualization and so on, this paper investigates the effect on the flow asymmetry by grit strips fixed on the forebody of a slender revolution body at high angles of attack in low turbulence wind tunnel. The results indicate that a "strip" type of grit can reduce the local side force and effectively improve the flow asymmetry; a "ring" type of grit can improve the flow separation state on the model surface but enforces the flow asymmetry; the effect of the combination of both strips on the flow pattern is complicated relatively. However, none of all theses strips of grit can completely eliminate the local side forces resulting from the flow asymmetry. The paper also demonstrates some forms and performance characteristics of the flow asymmetry at high angles of attack.